948 resultados para Maximal Rewriting of a Regular Language at a Regular Substitution


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This qualitative study was aimed at investigating foreign language teachers’ attitudes toward use of information and communication technology (ICT) in their instruction. The insight was gained through the reported experience of ICT implementation by teachers, in what way and for which purpose they refer to use of technology, what kind of support and training they are provided with, and what beliefs they express about the influence of ICT implementation. This case study took place in one of the training schools in Finland. Five teachers participated in semi-structured interviews through a face-to-face approach. The findings demonstrated positive attitudes of teachers toward integration of ICT. The teachers shared their opinions about positive influence that ICT implementation has on both teaching and learning processes. However, they also pointed out the negative sides of ICT use: distraction of the students from usage of technology and technical problems causing frustration to the teachers. In addition, the responses revealed that the teachers are provided with adequate training aimed at enhancing their qualification which is provided with well-timed technology support and colleagues’ collaboration facilitating an efficient and smooth pace of the teaching process. According to the teachers’ opinions ICT integration in education appeared to have changed the role of the teacher. Due to different alterations in the field of ICT development teachers are required to upgrade their skills. The paper concludes with the limitations of the study and the recommendations for conducting further research.

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This qualitative study was aimed at investigating foreign language teachers’ attitudes toward use of information and communication technology (ICT) in their instruction. The insight was gained through the reported experience of ICT implementation by teachers, in what way and for which purpose they refer to use of technology, what kind of support and training they are provided with, and what beliefs they express about the influence of ICT implementation. This case study took place in one of the training schools in Finland. Five teachers participated in semi-structured interviews through a face-to-face approach. The findings demonstrated positive attitudes of teachers toward integration of ICT. The teachers shared their opinions about positive influence that ICT implementation has on both teaching and learning processes. However, they also pointed out the negative sides of ICT use: distraction of the students from usage of technology and technical problems causing frustration to the teachers. In addition, the responses revealed that the teachers are provided with adequate training aimed at enhancing their qualification which is provided with well-timed technology support and colleagues’ collaboration facilitating an efficient and smooth pace of the teaching process. According to the teachers’ opinions ICT integration in education appeared to have changed the role of the teacher. Due to different alterations in the field of ICT development teachers are required to upgrade their skills. The paper concludes with the limitations of the study and the recommendations for conducting further research.

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This work is a description of Tajio, a Western Malayo-Polynesian language spoken in Central Sulawesi, Indonesia. It covers the essential aspects of Tajio grammar without being exhaustive. Tajio has a medium sized phoneme inventory consisting of twenty consonants and five vowels. The language does not have lexical (word) stress; rather, it has a phrasal accent. This phrasal accent regularly occurs on the penultimate syllable of an intonational phrase, rendering this syllable auditorily prominent through a pitch rise. Possible syllable structures in Tajio are (C)V(C). CVN structures are allowed as closed syllables, but CVN syllables in word-medial position are not frequent. As in other languages in the area, the only sequence of consonants allowed in native Tajio words are sequences of nasals followed by a homorganic obstruent. The homorganic nasal-obstruent sequences found in Tajio can occur word-initially and word-medially but never in word-final position. As in many Austronesian languages, word class classification in Tajio is not straightforward. The classification of words in Tajio must be carried out on two levels: the morphosyntactic level and the lexical level. The open word classes in Tajio consist of nouns and verbs. Verbs are further divided into intransitive verbs (dynamic intransitive verbs and statives) and dynamic transitive verbs. Based on their morphological potential, lexical roots in Tajio fall into three classes: single-class roots, dual-class roots and multi-class roots. There are two basic transitive constructions in Tajio: Actor Voice and Undergoer Voice, where the actor or undergoer argument respectively serves as subjects. It shares many characteristics with symmetrical voice languages, yet it is not fully symmetric, as arguments in AV and UV are not equally marked. Neither subjects nor objects are marked in AV constructions. In UV constructions, however, subjects are unmarked while objects are marked either by prefixation or clitization. Evidence from relativization, control and raising constructions supports the analysis that AV and UV are in fact transitive, with subject arguments and object arguments behaving alike in both voices. Only the subject can be relativized, controlled, raised or function as the implicit subject of subjectless adverbial clauses. In contrast, the objects of AV and UV constructions do not exhibit these features. Tajio is a predominantly head-marking language with basic A-V-O constituent order. V and O form a constituent, and the subject can either precede or follow this complex. Thus, basic word order is S-V-O or V-O-S. Subject, as well as non-subject arguments, may be omitted when contextually specified. Verbs are marked for voice and mood, the latter of which is is obligatory. The two values distinguished are realis and non-realis. Depending on the type of predicate involved in clause formation, three clause types can be distinguished: verbal clauses, existential clauses and non-verbal clauses. Tajio has a small number of multi-verbal structures that appear to qualify as serial verb constructions. SVCs in Tajio always include a motion verb or a directional.

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The study carried out in this thesis is devoted to spectral analysis of systems of PDEs related also with quantum physics models. Namely, the research deals with classes of systems that contain certain quantum optics models such as Jaynes-Cummings, Rabi and their generalizations that describe light-matter interaction. First we investigate the spectral Weyl asymptotics for a class of semiregular systems, extending to the vector-valued case results of Helffer and Robert, and more recently of Doll, Gannot and Wunsch. Actually, the asymptotics by Doll, Gannot and Wunsch is more precise (that is why we call it refined) than the classical result by Helffer and Robert, but deals with a less general class of systems, since the authors make an hypothesis on the measure of the subset of the unit sphere on which the tangential derivatives of the X-Ray transform of the semiprincipal symbol vanish to infinity order. Abstract Next, we give a meromorphic continuation of the spectral zeta function for semiregular differential systems with polynomial coefficients, generalizing the results by Ichinose and Wakayama and Parmeggiani. Finally, we state and prove a quasi-clustering result for a class of systems including the aforementioned quantum optics models and we conclude the thesis by showing a Weyl law result for the Rabi model and its generalizations.

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The price-wedge method yields a tariff-equivalent estimate of technical barriers to trade (TBT). An extension of this method accounts for imperfect substitution between domestic and imported goods and incorporates recent findings on trade costs. We explore the sensitivity of this revamped TBT estimate to its key determinants (substitution elasticity, preference for home good, and trade cost). We use the augmented approach to investigate the ongoing US-Japan apple trade dispute and find that removing the Japanese TBT would yield limited export gains to the United States. We then draw policy implications of our findings.

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Recombinant secretory immunoglobulin A containing a bacterial epitope in domain I of the secretory component (SC) moiety can serve as a mucosal delivery vehicle triggering both mucosal and systemic responses (Corthésy, B., Kaufmann, M., Phalipon, A., Peitsch, M., Neutra, M. R., and Kraehenbuhl, J.-P. (1996) J. Biol. Chem. 271, 33670-33677). To load recombinant secretory IgA with multiple B and T epitopes and extend its biological functions, we selected, based on molecular modeling, five surface-exposed sites in domains II and III of murine SC. Loops predicted to be exposed at the surface of SC domains were replaced with the DYKDDDDK octapeptide (FLAG). Another two mutants were obtained with the FLAG inserted in between domains II and III or at the carboxyl terminus of SC. As shown by mass spectrometry, internal substitution of the FLAG into four of the mutants induced the formation of disulfide-linked homodimers. Three of the dimers and two of the monomers from SC mutants could be affinity-purified using an antibody to the FLAG, mapping them as candidates for insertion. FLAG-induced dimerization also occurred with the polymeric immunoglobulin receptor (pIgR) and might reflect the so-far nondemonstrated capacity of the receptor to oligomerize. By co-expressing in COS-7 cells and epithelial Caco-2 cells two pIgR constructs tagged at the carboxyl terminus with hexahistidine or FLAG, we provide the strongest evidence reported to date that the pIgR dimerizes noncovalently in the plasma membrane in the absence of polymeric IgA ligand. The implication of this finding is discussed in terms of IgA transport and specific antibody response at mucosal surfaces.

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ABSTRACT Changes in carbon stocks in different compartments of soil organic matter of a clayey Latossolo Vermelho Distrófico (Typic Haplustox), caused by the substitution of native savanna vegetation (cerrado sensu stricto) by agroecosystems, were assessed after 31 years of cultivation. Under native vegetation, a stock of 164.5 Mg ha-1 C was estimated in the 0.00-1.00 m layer. After 31 years of cultivation, these changes in soil C stocks were detected to a depth of 0.60 m. In the case of substitution of cerrado sensu stricto by no-tillage soybean-corn rotation, a reduction of at least 11 % of the soil C pools was observed. However, the adoption of no-tillage as an alternative to tillage with a moldboard plow (conventional system) reduced CO2 emissions by up to 12 %.

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The iron ore pelletizing process consumes high amounts of energy, including nonrenewable sources, such as natural gas. Due to fossil fuels scarcity and increasing concerns regarding sustainability and global warming, at least partial substitution by renewable energy seems inevitable. Gasification projects are being successfully developed in Northern Europe, and large-scale circulating fluidized bed biomass gasifiers have been commissioned in e.g. Finland. As Brazil has abundant biomass resources, biomass gasification is a promising technology in the near future. Biomasses can be converted into product gas through gasification. This work compares different technologies, e.g. air, oxygen and steam gasification, focusing on the use of the product gas in the indurating machine. The use of biosynthetic natural gas is also evaluated. Main parameters utilized to assess the suitability of product gas were adiabatic flame temperature and volumetric flow rate. It was found that low energy content product gas could be utilized in the traveling grate, but it would require burner’s to be changed. On the other hand, bio-SGN could be utilized without any adaptions. Economical assessment showed that all gasification plants are feasible for sizes greater than 60 MW. Bio-SNG production is still more expensive than natural gas in any case.

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CuAlO2 has been examined as a potential luminescent material by substituting Eu for Al cations in the delafossite structure. CuAlO2:Eu3+ nanofibers have been prepared via electrospinning for the ease of mitigating synthesis requirements and for future optoelectronics and emerging applications. Single-phase CuAlO2 fibers could be obtained at a temperature of 1100 °C in air. The Eu was successfully doped in the delafossite structure and two strong emission bands at ~405 and 610 nm were observed in the photoluminescence spectra. These bands are due to the intrinsic near-band-edge transition of CuAlO2 and the f-f transition of the Eu3+ activator, respectively. Further electrical characterization indicated that these fibers exhibit semiconducting behavior and the introduction of Eu could act as band-edge modifiers, thus changing the thermal activation energies. In light of this study, CuAlO2:Eu3+ fibers with both strong photoluminescence and p-type conductivity could be produced by tailoring the rare earth doping concentrations.

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ABSTRACT: Changes in carbon stocks in different compartments of soil organic matter of a clayey Latossolo Vermelho Distrófico (Typic Haplustox), caused by the substitution of native savanna vegetation (cerrado sensu stricto) by agroecosystems, were assessed after 31 years of cultivation. Under native vegetation, a stock of 164.5 Mg ha-1 C was estimated in the 0.00-1.00 m layer. After 31 years of cultivation, these changes in soil C stocks were detected to a depth of 0.60 m. In the case of substitution of cerrado sensu stricto by no-tillage soybean-corn rotation, a reduction of at least 11 % of the soil C pools was observed. However, the adoption of no-tillage as an alternative to tillage with a moldboard plow (conventional system) reduced CO2 emissions by up to 12 %.

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Background: Concerted evolution is normally used to describe parallel changes at different sites in a genome, but it is also observed in languages where a specific phoneme changes to the same other phoneme in many words in the lexicon—a phenomenon known as regular sound change. We develop a general statistical model that can detect concerted changes in aligned sequence data and apply it to study regular sound changes in the Turkic language family. Results: Linguistic evolution, unlike the genetic substitutional process, is dominated by events of concerted evolutionary change. Our model identified more than 70 historical events of regular sound change that occurred throughout the evolution of the Turkic language family, while simultaneously inferring a dated phylogenetic tree. Including regular sound changes yielded an approximately 4-fold improvement in the characterization of linguistic change over a simpler model of sporadic change, improved phylogenetic inference, and returned more reliable and plausible dates for events on the phylogenies. The historical timings of the concerted changes closely follow a Poisson process model, and the sound transition networks derived from our model mirror linguistic expectations. Conclusions: We demonstrate that a model with no prior knowledge of complex concerted or regular changes can nevertheless infer the historical timings and genealogical placements of events of concerted change from the signals left in contemporary data. Our model can be applied wherever discrete elements—such as genes, words, cultural trends, technologies, or morphological traits—can change in parallel within an organism or other evolving group.

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Premise of the study: The phloem is a plant tissue with a critical role in plant nutrition and signaling. However, little is still known about the evolution of this tissue. In lianas of the Bignoniaceae, two distinct types of phloem coexist: a regular and a variant phloem. The cells associated with these two phloem types are known to be anatomically different; however, it is still unclear what steps were involved in the evolution of such differences. Methods: Here we studied the anatomical development of the regular and variant phloem in representatives of all 21 genera of Bignonieae and used a phylogenetic framework to investigate the timing of changes associated with the evolution of each phloem type. Key results: We found that the variant phloem always appears in a determinate location, between the leaf orthostichies. Furthermore, the variant phloem was mostly occupied by very wide sieve tubes and generally included a higher concentration of fibers, indicating an increase in conduction and mechanical support. On the other hand, the regular phloem included much more parenchyma, more and wider rays, and tiny sieve tubes that resembled terminal sieve tubes from plants with seasonal formation of vascular tissues; these findings suggest reduced conduction and higher storage capacity in the regular phloem. Conclusions: Overall, differences between the regular and variant phloem increased over time, leading to further specialization in conduction in the variant phloem and an increase in storage specialization in the regular phloem.

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Aims: To investigate the effects of a 6-month supplementation with calcium and cholecalciferol on biochemical parameters and muscle strength of institutionalized elderly. Methods: This prospective, double-blind, placebo-controlled, randomized trial included Brazilian institutionalized people 6 60 years of age receiving a 6-month supplementation ( December to May) of daily calcium plus monthly placebo (calcium/placebo group) or daily calcium plus oral cholecalciferol (150,000 IU once a month during the first 2 months, followed by 90,000 IU once a month for the last 4 months; calcium/vitamin D group). Fasting blood samples for 25-(OH) D, PTH and calcium determination were collected (n = 56) and muscle tests were performed ( n = 46) to measure the strength of hip flexors (SHF) and knee extensors (SKE) before ( baseline) and after the 6-month intervention ( 6 months). Results: Due to seasonal variations, serum 25( OH) D significantly enhanced in both groups after treatment, but the calcium/vitamin D group had significantly higher 25-(OH) D levels than the calcium/placebo group (84 vs. 33%, respectively; p < 0.0001). No cases of hypercalcemia were observed. While the calcium/placebo group showed no improvement in SHF and SKE at 6 months (p = 0.93 and p = 0.61, respectively), SHF was increased in the calcium/vitamin D group by 16.4% (p = 0.0001) and SKE by 24.6% (p = 0.0007). Conclusions: The suggested cholecalciferol supplementation was safe and efficient in enhancing 25(OH)D levels and lower limb muscle strength in the elderly, in the absence of any regular physical exercise practice. Copyright (C) 2009 S. Karger AG, Basel

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This paper proposes a simple high-level programming language, endowed with resources that help encoding self-modifying programs. With this purpose, a conventional imperative language syntax (not explicitly stated in this paper) is incremented with special commands and statements forming an adaptive layer specially designed with focus on the dynamical changes to be applied to the code at run-time. The resulting language allows programmers to easily specify dynamic changes to their own program`s code. Such a language succeeds to allow programmers to effortless describe the dynamic logic of their adaptive applications. In this paper, we describe the most important aspects of the design and implementation of such a language. A small example is finally presented for illustration purposes.

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The research reported here draws on a study of five teenagers from a Dinka-speaking community of Sudanese settling in Australia. A range of factors including language proficiency, social network structure and language attitudes are examined as possible causes for the variability of language use. The results and discussion illustrate how the use of a triangular research approach captured the complexity of the participants' language situation and was critical to developing a full understanding of the interplay of factors influencing the teens' language maintenance and shift in a way that no single method could. Further, it shows that employment of different methodologies allowed for flexibility in data collection to ensure the fullest response from participants. Overall, this research suggests that for studies of non-standard communities, variability in research methods may prove more of a strength that the use of standardised instruments and approaches.