991 resultados para normal forms


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Conformational preferences of thiocarbonohydrazide (H2NNHCSNHNH2) in its basic and N,N′-diprotonated forms are examined by calculating the barrier to internal rotation around the C---N bonds, using the theoretical LCAO—MO (ab initio and semiempirical CNDO and EHT) methods. The calculated and experimental results are compared with each other and also with values for N,N′-dimethylthiourea which is isoelectronic with thiocarbonohydrazide. The suitability of these methods for studying rotational isomerism seems suspect when lone pair interactions are present.

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"The Art of Sympathy: Forms of Moral and Emotional Persuasion" in Fiction is an interdisciplinary study that looks closely at the ways that stories evoke sympathy, and the significance of this emotion for the development of moral attitudes and awareness. By linking readers' emotional responses to fiction with the potential impact of such responses on "the moral imagination," the study builds on empirical research conducted by literary scholars and psychologists into the emotional effects of reading fiction, as well as social psychological research into the connections between empathy/sympathy and moral development. I first investigate the dynamics of readers beliefs regarding characters in fictional narratives, and the nature of the emotions that they may experience as a result of those beliefs. The analysis demonstrates that there are important similarities between real emotions and emotions generated by fiction. Recognizing these similarities, I claim, can help us to conceptualize the nature of sympathetic responses to fictional characters. Building on these assertions, I then draw on research from social psychology and philosophy to develop a comprehensive definition of sympathy and to clarify the ways in which sympathy operates, both in people s daily lives and in readers sympathetic responses to fictional characters. Having established this definition and delineated its practical implications, I then examine how particular stories, through a variety of narrative techniques, persuade readers to feel sympathy for characters who are unsympathetic in certain ways. In order to verify my claims about the impact of these stories on readers emotions, I also review the results of tests that I conducted with nearly 200 adolescent readers. Through these tests, which were constructed and scored according to methods prevalent in social psychological research, it was determined that a majority of readers felt sympathy for the protagonists in two of the stories included in the study. These results were combined with data from an additional test, a standard measure of empathy and sympathy in the field of social psychology. The cross-tabulation of these results suggests that there was not a strong connection between readers responses and their general tendencies to feel sympathy for others. This finding would appear to support my hypotheses regarding the sympathetic persuasiveness of the stories in question. In light of these results, finally, I consider the potential contribution that fiction can make to adolescent emotional and moral development and the implications of that potential for future language arts curricula in the schools. In particular, I suggest the pedagogical importance of providing adolescents with opportunities to engage with the lives of fictional characters, and especially to experience feelings of sympathy for individuals towards whom they ordinarily might feel aversion.

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We study the renormalization group flows of the two terminal conductance of a superconducting junction of two Luttinger liquid wires. We compute the power laws associated with the renormalization group flow around the various fixed points of this system using the generators of the SU(4) group to generate the appropriate parametrization of an matrix representing small deviations from a given fixed point matrix [obtained earlier in S. Das, S. Rao, and A. Saha, Phys. Rev. B 77, 155418 (2008)], and we then perform a comprehensive stability analysis. In particular, for the nontrivial fixed point which has intermediate values of transmission, reflection, Andreev reflection, and crossed Andreev reflection, we show that there are eleven independent directions in which the system can be perturbed, which are relevant or irrelevant, and five directions which are marginal. We obtain power laws associated with these relevant and irrelevant perturbations. Unlike the case of the two-wire charge-conserving junction, here we show that there are power laws which are nonlinear functions of V(0) and V(2kF) [where V(k) represents the Fourier transform of the interelectron interaction potential at momentum k]. We also obtain the power law dependence of linear response conductance on voltage bias or temperature around this fixed point.

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The prevalence and developmental course of supposed ‘secret language’ was examined in a cohort of twins and closely spaced singletons pairs, with systematic assessments at 20 months and again at 36 months. Two forms of apparent ‘secret language’ were examined: (1) shared understanding—speech directed generally but unintelligible to the parent, although apparently clearly understood within the child pair, and (2) private language directed exclusively to the other twin/sibling—not intelligible to the parent, but apparently clearly understood and used only within the child pair. Both occurred in singleton pairs, but the rate was much higher in twins. In most cases it seemed to be a developmental phenomenon occurring in the second year of life with the emergence of immature speech, and decreasing considerably over the next 16 months. A small group of children, primarily male twins, was reported to use a private language at 36 months. This group had poorer cognitive and language functioning, and was characterized by highly dependent relationships. Some aspects of the twins’ home environment were less stimulating and less responsive, most probably reflecting the abilities and relationships of the children. A follow-up of these children when they were ~6 years of age showed that language outcome was poor for the subgroup (n = 4) who did not develop normal language alongside the use of a private language.

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Purpose: Presence of neurophysiological abnormalities in dyslexia has been a conflicting issue. This study was performed to evaluate the role of sensory visual deficits in the pathogenesis of dyslexia. Methods: Pattern visual evoked potentials (PVEP) were recorded in 72 children including 36 children with dyslexia and 36 children without dyslexia (controls) who were matched for age, sex and intelligence. Two check sizes of 15 and 60 min of arc were used with temporal frequencies of 1.5 Hz for transient and 6 Hz for steady‑state methods. Results: Mean latency and amplitude values for 15 min arc and 60 min arc check sizes using steady state and transient methods showed no significant difference between the two study groups (P values: 0.139/0.481/0.356/0.062).Furthermore, no significant difference was observed between two methods of PVEPs in dyslexic and normal children using 60min arc with high contrast(Pvalues: 0.116, 0.402, 0.343 and 0.106). Conclusion: The sensitivity of PVEP has high validity to detect visual deficits in children with dyslexic problem. However, no significant difference was found between dyslexia and normal children using high contrast stimuli.

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The extragalactic diffuse emission at gamma-ray energies has interesting cosmological implications since these photons suffer little or no attenuation during their propagation from the site of origin. The emission could originate from either truly diffuse processes or from unresolved point sources such as AGNs, normal galaxies and starburst galaxies. Here, we examine the unresolved point source origin of the extragalactic gamma-ray background emission from normal galaxies and starburst galaxies. gamma-ray emission from normal galaxies is primarily coming from cosmic-ray interactions with interstellar matter and radiation (similar to 90%) along with a small contribution from discrete point sources (similar to 10%). Starburst galaxies are expected to have enhanced supernovae activity which leads to higher cosmic-ray densities, making starburst galaxies sufficiently luminous at gamma-ray energies to be detected by the current gamma-ray mission(Fermi Gamma-ray Space Telescope).

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he Dirac generator formalism for relativistic Hamiltonian dynamics is reviewed along with its extension to constraint formalism. In these theories evolution is with respect to a dynamically defined parameter, and thus time evolution involves an eleventh generator. These formulations evade the No-Interaction Theorem. But the incorporation of separability reopens the question, and together with the World Line Condition leads to a second no-interaction theorem for systems of three or more particles. Proofs are omitted, but the results of recent research in this area is highlighted.

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Ultrasound screening is now a routine procedure which forms part of antenatal care provision. Within this routine context ultrasound technology has been found to be generally acceptable and indeed is positively demanded by many women. This paper raises the question whether the routine presentation of ultrasound implicitly conveys the message that is use in antenatal care is both valuable and safe. It examines women's views of ultrasound technology beyond a routine context. In a study designed to examine women's reactions to cerebral ultrasound on their normal term infants mothers were asked their views and knowledge of ultrasound and a comparison with their antenatal experience of ultrasound was elicited. A generalized concern about ultrasound techniques was found to underlie many of the women's comments. This raised questions concerning the current practice in the presentation of ultrasound to women attending for antenatal care.

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The ribosomal DNA internal transcribed spacer region was amplified and sequenced from a selection of specimens of the Sporobolus smut Ustilago sporoboli-indici. Phylogenetic comparison with other Ustilago and Sporisorium species revealed strong support for an evolutionary radiation of Ustilago species infecting the Chloridoideae and Pooideae, of which U. sporoboli-indici forms a major lineage. Comparisons are made with other groups of plant pathogenic fungi, and it is concluded that phylogenetic analyses of potential biocontrol agents are useful for identifying pathogens that are derived from evolutionary lineages that parasitize a wide range of unrelated plants. Such pathogens are less desirable as biocontrol agents as they may have a greater likelihood of infecting plants outside their normal host ranges.

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A nucleosome forms a basic unit of the chromosome structure. A biologically relevant question is how much of the nucleosomal conformational space is accessible to protein-free DNA, and what proportion of the nucleosomal conformations are induced by bound histones. To investigate this, we have analysed high resolution xray crystal structure datasets of DNA in protein-free as well as protein-bound forms, and compared the dinucleotide step parameters for the two datasets with those for high resolution nucleosome structures. Our analysis shows that most of the dinucleotide step parameter values for the nucleosome structures lie within the range accessible to protein-free DNA, indirectly indicating that the histone core plays more of a stabilizing role. The nucleosome structures are observed to assume smooth and nearly planar curvature, implying that ‘normal’ B-DNA like parameters can give rise to a curved geometry at the gross structural level. Different nucleosome

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In recent years there has been an upsurge of interest in the study of organic reactions in the solid state. It is now realised that the crystalline matrix provides an extra-ordinary spatial control on the initiation and progress of these reactions. Electronic and dipolar effects which are important in solution are replaced by structural and geometric effects in solids. These 'spatial' or 'topochemical' aspects are important in understanding the mechanistic details of the reaction. In our laboratory, the thermally induced acyl migration in salicylamides from 0- to N- position in the solid state has been under study (Scheme 1). The structures of the acetyl and benzoyl derivatives (Ia,IIa, Ib and IIb) have been reported.

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The normal-mode solution to the problem of acoustic wave propagation in an isovelocity ocean with a wavy surface is considered. The surface wave amplitude is assumed to be small compared to the acoustic wavelength, and the method of multiple scales is employed to study the interaction between normal-mode acoustic waves and the surface waves. A nonresonant interaction causes small fluctuations of the amplitude and phase of the acoustic wave at a rate dependent on the frequency of the surface wave. Backscatter occurs if the wavenumber of the surface wave is larger than that of the acoustic wave. The interaction becomes resonant if appropriate phase-matching conditions are satisfied. In this case, two acoustic normal modes get coupled, resulting in a large-scale periodic exchange of energy from one mode to another.

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From the field to the academic sphere how teachers professional identities and roles have changed in post-war Finland This study explores teacher autobiographies. The span of the writings extends mainly from the Second World War to the new millennium. The autobiographers are mostly elementary and secondary school teachers in Finland, although there are a few who have worked in vocational schools, polytechnic institutes or one of the various adult education centres. The researcher is aware of the diversity among those educational institutions and their teachers, but wanted to concentrate on similarities rather than differences. The autobiographers have been explored with four different research questions in view. The first was to identify professional and personal elements and themes mentioned by teachers in writing about themselves. The second was to identify the factors that have affected those elements and themes. The third was to examine the kinds of literary forms teachers used in their autobiographies. The fourth was the most crucial and an endeavour to connect the previous questions: how teachers professional identities and roles have changed during the period studied. In the first five chapters the teachers voices come through clearly. Two of these chapters are organized in chronological order. The first is about childhood, youth and the time spent in school, the second deals with the years studying in university or teachers college and finally being recruited to the teachers. In these chapters the rural background of many teachers stands out, an issue that also emerged symbolically or de facto in the autobiographies. The chronological scheme changes to a thematic order, in which social matters (students, parents, colleagues) and teachers working circumstances are dealt with. Four selected autobiographies are examined closely. In these autobiographies five different types of teacher narratives can be identified. To begin with, teachers stressed their vocation, which is quite a normal work orientation for those working in the educational field. Others emphasised how they were looking for professional development; a few wrote about personal advancement as well. There are also narratives by teachers who simply drifted into the profession of teaching, while a few teachers felt unwelcome in their own schools. As for the changes that teachers have witnessed, there are also some themes that are widely shared. Most pointed out how the teacher has become more foster parent than educator, as real parents have withdrawn from their responsibilities of raising children. This theme was frequently broached, although attitude towards it and ways of handling the phenomenon differed substantially. Teachers also stressed how their profession has lost the aura and prestige it once had. At the same time teachers are being expected to collaborate more with their colleagues, which is not in line with the centuries-old tradition of working alone. Teachers seem to be in a state of flux, buffeted by elements of stability and change interacting simultaneously. Many teachers are demanding a re-examination of their working reality. Teachers long and intimate relationship with society and the state may be at a crossroads. Key words: teachers professional identity and role, autobiographical study, post-war Finland