On the Hardness of a New Boron Phase, Orthorhombic {\gamma}-B28

Measurements of the hardness of a new high-pressure boron phase, orthorhombic {\gamma}-B28, are reported. According to the data obtained, {\gamma}-B28 has the highest hardness (~50 GPa) of all known crystalline modifications of boron

The origin of human chromosome 2 analyzed by comparative chromosome mapping with a DNA microlibrary

Fluorescencein situ hybridization (FISH) of microlibraries established from distinct chromosome subregions can test the evolutionary conservation of chromosome bands as well as chromosomal rearrangements that occurred during primate evolution and will help to clarify phylogenetic relationships. We used a DNA library established by microdissection and microcloning from the entire long arm of human chromosome 2 for fluorescencein situ hybridization and comparative mapping of the chromosomes of human, great apes (Pan troglodytes, Pan paniscus, Gorilla gorilla, Pongo pygmaeus) and Old World monkeys (Macaca fuscata andCercopithecus aethiops). Inversions were found in the pericentric region of the primate chromosome 2p homologs in great apes, and the hybridization pattern demonstrates the known phylogenetically derived telomere fusion in the line that leads to human chromosome 2. The hybridization of the 2q microlibrary to chromosomes of Old World monkeys gave a different pattern from that in the gorilla and the orang-utan, but a pattern similar to that of chimpanzees. This suggests convergence of chromosomal rearrangements in different phylogenetic lines

EFL students' perspectives on English: the (widening) gap between ideals and practices Perspectivas de estudantes de língua estrangeira sobre o inglês: a (grande) lacuna entre ideais e práticas

This paper is based on a survey into perspectives on the English language conducted in a MA in TEFL program in a Croatian University. In the study we examine non-native student-teachers' attitudes towards English and explore four key issues: a) which varieties of English are preferred, b) how the notion of English as an International Language is conceptualized, c) how attitudes about English inform teaching and learning, and d) to what extent the sociocultural context informs attitudes about English. In the English department, there is no articulated policy toward English, yet there appears to be a strong attachment to native-speaker norms. However, with the internationalization of English and the changing ownership of the language, in recent years, much debate has arisen over the native-speaker ideal (HOLLIDAY, 2005; MCKAY, 2002). The English language is used primarily by non-native speakers to communicate with non-native speakers but it appears that this notion has had little impact on teaching and learning (see JENKINS, 2007). We see this gap as an important, and relatively underexplored issue, which merits more interest in English studies. We conclude that, in this context, perceptions of English are still formed by native-speaker norms, and lack of policy on the English language, in fact, supports native-speaker policy.<br>Este artigo baseia-se em um levantamento de perspectivas sobre a língua inglesa, conduzido com alunos de um programa de Mestrado em Ensino da Língua Inglesa de uma universidade croata. No estudo, examinamos as atitudes dos alunos-professores em relação ao inglês e exploramos quatro questões-chave: a) quais variedades do inglês são preferidas, b) como a noção de inglês como língua internacional é conceptualizada, c) como atitudes em relação ao inglês informam o ensino e a aprendizagem e d) o quanto o contexto sociocultural informa as atitudes em relação ao inglês. No Departamento de Inglês da universidade não há política articulada em relção ao inglês, porém parece haver um vínculo forte com normas nativas. Entretanto, com a internacionalização do inglês e as mudanças na propriedade da língua, em anos mais recentes, muitos debates vêm surgindo acerca do falante nativo ideal (HOLLIDAY, 2005; MCKAY, 2002). A língua inglesa é usada primariamente por falantes não nativos, mas aparentemente esta noção tem pouco impacto no ensino e na aprendizagem (ver JENKINS, 2007). Nós vemos esta lacuna como uma questão importante e pouco explorada, não obstante meritória de mais interesse nos estudos da língua inglesa. Concluímos que, nesse contexto, as percepções sobre o inglês ainda são formadas por normas nativas e que a falta de políticas sobre a língua inglesa apoiam uma política do falante nativo

Plasticity of orientation preference maps in the visual cortex of adult cats

In contrast to the high degree of experience-dependent plasticity usually exhibited by cortical representational maps, a number of experiments performed in visual cortex suggest that the basic layout of orientation preference maps is only barely susceptible to activity-dependent modifications. In fact, most of what we know about activity-dependent plasticity in adults comes from experiments in somatosensory, auditory, or motor cortex. Applying a stimulation protocol that has been proven highly effective in other cortical areas, we demonstrate here that enforced synchronous cortical activity induces major changes of orientation preference maps (OPMs) in adult cats. Combining optical imaging of intrinsic signals and electrophysiological single-cell recordings, we show that a few hours of intracortical microstimulation (ICMS) lead to an enlargement of the cortical representational zone at the ICMS site and an extensive restructuring of the entire OPM layout up to several millimeters away, paralleled by dramatic changes of pinwheel numbers and locations. At the single-cell level, we found that the preferred orientation was shifted toward the orientation of the ICMS site over a region of up to 4 mm. Our results show that manipulating the synchronicity of cortical activity locally without invoking training, attention, or reinforcement, OPMs undergo large-scale reorganization reminiscent of plastic changes observed for nonvisual cortical maps. However, changes were much more widespread and enduring. Such large-scale restructuring of the visual cortical networks indicates a substantial capability for activity-dependent plasticity of adult visual cortex and may provide the basis for cognitive learning processes