Strategy instruction in listening for lower-intermediate learners of French

Second language listening has historically proved to be a difficult skill. Strategy instruction studies have sought to bring about improvements in subjects’ listening but with mixed results. This lack of success might be due to the nature of listening strategy theory and its influence on conceptualizations of listening strategy instruction. The current study, based on an initial descriptive investigation of a specific population of learners, measured the effects of strategy instruction on both the listening performance and self-efficacy of 68 lower-intermediate learners of French in England, against a comparison group. Moreover, the effects of high- and low-scaffolded interventions were compared. Results suggest that the program improved listening proficiency and learners’ confidence about listening. Implications for pedagogy and strategy theory are discussed.

Role of nesting resources in organising diverse bee communities in a Mediterranean landscape

1. The habitat components determining the structure of bee communities are well known when considering foraging resources; however, there is little data with respect to the role of nesting resources. 2. As a model system this study uses 21 diverse bee communities in a Mediterranean landscape comprising a variety of habitats regenerating after fire. The findings clearly demonstrate that a variety of nesting substrates and nest building materials have key roles in organising the composition of bee communities. 3. The availability of bare ground and potential nesting cavities were the two primary factors influencing the structure of the entire bee community, the composition of guilds, and also the relative abundance of the dominant species. Other nesting resources shown to be important include availability of steep and sloping ground, abundance of plant species providing pithy stems, and the occurrence of pre-existing burrows. 4. Nesting resource availability and guild structure varied markedly across habitats in different stages of post-fire regeneration; however, in all cases, nest sites and nesting resources were important determinants of bee community structure.

A platform for supporting micro-collaborations in a diverse device environment

Collaborative software is usually thought of as providing audio-video conferencing services, application/desktop sharing, and access to large content repositories. However mobile device usage is characterized by users carrying out short and intermittent tasks sometimes referred to as 'micro-tasking'. Micro-collaborations are not well supported by traditional groupware systems and the work in this paper seeks out to address this. Mico is a system that provides a set of application level peer-to-peer services for the ad-hoc formation and facilitation of collaborative groups across a diverse mobile device domain. The system builds on the Java ME bindings of the JXTA P2P protocols, and is designed with an approach to use the lowest common denominators that are required for collaboration between varying degrees of mobile device capability. To demonstrate how our platform facilitates application development, we built an exemplary set of demonstration applications and include code examples here to illustrate the ease and speed afforded when developing collaborative software with Mico.

Diverse mariner-like elements in fig wasps

Mariner transposable elements are widespread and diverse in insects. We screened 10 species of fig wasps (Hymenoptera: Agaonidae) for mariner elements. All 10 species harbour a large diversity of mariner elements, most of which have interrupted reading frames in the transposase gene region, suggesting that they are inactive and ancient. We sequenced two full-length mariner elements and found evidence to suggest that they are inserted in the genome at a conserved region shared by other hymenopteran taxa. The association between mariner elements and fig wasps is old and dominated by vertical transmission, suggesting that these 'selfish genetic elements' have evolved to impart only very low costs to their hosts.

Diverse signalling by different chemokines through the chemokine receptor CCR5

We have investigated the signalling properties of the chemokine receptor, CCR5, using several assays for agonism: stimulation of changes in intracellular Ca2+ or CCR5 internalisation in CHO cells expressing CCR5 or stimulation of [S-35]GTP gamma S binding in membranes of CHO cells expressing CCR5. Four isoforms of the chemokine CCL3 with different amino termini (CCL3, CCL3(2-70), CCL3(5-70), CCL3L1) were tested in these assays in order to probe structure/activity relationships. Each isoform exhibited agonism. The pattern of agonism (potency, maximal effect) was different in the three assays, although the rank order was the same with CCL3L1 being the most potent and efficacious. The data show that the amino terminus of the chemokine is important for signalling. A proline at position 2 (CCL3L1) provides for high potency and efficacy but the isoform with a serine at position 2 (CCL3(2-70)) is as efficacious in some assays showing that the proline is not the only determinant of high efficacy. We also increased the sensitivity of CCR5 signalling by treating cells with sodium butyrate, thus increasing the receptor/G protein ratio. This allowed the detection of a change in intracellular Ca2+ after treatment with CCL7 and Met-RANTES showing that these ligands possess measurable but low efficacy. This study therefore shows that sodium butyrate treatment increases the sensitivity of signalling assays and enables the detection of efficacy in ligands previously considered as antagonists. The use of different assay systems, therefore, provides different estimates of efficacy for some ligands at this receptor. (c) 2006 Elsevier Inc. All rights reserved.

Immigration, species radiation and extinction in a highly diverse songbird lineage: white-eyes on Indian Ocean islands

Molecular phylogenetic hypotheses of species-rich lineages in regions where geological history can be reliably inferred may provide insights into the scale of processes driving diversification. Here we sample all extant or recently extinct white-eye (Zosterops) taxa of the southwest Indian Ocean, combined with samples from all principal continental lineages. Results support a high dispersal capability, with at least two independent continental sources for white-eyes of the region. An early (within 1.8 million years ago) expansion into the Indian Ocean may have originated either from Asia or Africa; the three resulting lineages show a disparate distribution consistent with considerable extinction following their arrival. Africa is supported as the origin of a later expansion into the region (within 1.2 million years ago). On two islands, a pair of Zosterops species derived from independent immigrations into the Indian Ocean co-occur or may have formerly co-occurred, providing strong support for their origin by double-island colonization rather than within-island (sympatric or microallopatric) speciation. On Mauritius and La Reunion, phylogenetic placement of sympatric white-eyes allow us to rule out a scenario in which independent within-island speciation occurred on both islands; one of the species pairs must have arisen by double colonization, while the other pair is likely to have arisen by the same mechanism. Long-distance immigration therefore appears to be responsible for much of the region's white-eye diversity. Independent immigrations into the region have resulted in lineages with mutually exclusive distributions and it seems likely that competition with congeneric species, rather than arrival frequency, may limit present-day diversity.

Cupins: the most functionally diverse protein superfamily?

The cupin superfamily of proteins, named on the basis of a conserved β-barrel fold (‘cupa’ is the Latin term for a small barrel), was originally discovered using a conserved motif found within germin and germin-like proteins from higher plants. Previous analysis of cupins had identified some 18 different functional classes that range from single-domain bacterial enzymes such as isomerases and epimerases involved in the modification of cell wall carbohydrates, through to two-domain bicupins such as the desiccation-tolerant seed storage globulins, and multidomain transcription factors including one linked to the nodulation response in legumes. Recent advances in comparative genomics, and the resolution of many more 3-D structures have now revealed that the largest subset of the cupin superfamily is the 2-oxyglutarate-Fe2+ dependent dioxygenases. The substrates for this subclass of enzyme are many and varied and in total amount to probably 50–100 different biochemical reactions, including several involved in plant growth and development. Although the majority of enzymatic cupins contain iron as an active site metal, other members contain either copper, zinc, cobalt, nickel or manganese ions as a cofactor, with each cofactor allowing a different type of chemistry to occur within the conserved tertiary structure. This review discusses the range of structures and functions found in this most diverse of superfamilies.

Listening comprehension: the learners' perspective

This paper reports on the findings of an investigation into the perceptions held by English students aged 16–18 years regarding listening comprehension in French and how they view the reasons behind their success or lack of it in this skill. The study suggests that listening comprehension is the skill in which students in the post-compulsory phase of education feel they have achieved the least success. The main problems highlighted by learners were dealing adequately with the speed of delivery of texts, making out individual words in a stream of spoken French, and making sense of any words identified. Furthermore, most learners attributed their difficulties in listening to their own supposed low ability in the skill and to the difficulty of the listening tasks and texts set, with little awareness shown regarding the role played by ineffective listening strategies or skill application. Suggestions are made for addressing problems regarding how students listen and their attitudes towards listening comprehension.

Establishing a sexual identity: case studies of learners with autism and learning difficulties

The physical and emotional changes that occur in adolescence are part of the process of sexual maturity. These changes occur irrespective of ability and are often aligned with psychological and social factors. When the nature of a disability has an inherent limitation in social awareness, as is the case for individuals with autism, the achievement of personal sexual identity can become much more complex. Challenges in supporting individuals in this respect can be caused by the sensitive aspects of inappropriate behaviour, the abstract nature of teaching the topic, and the general reluctance on the part of parents and staff to discuss sexuality in individuals with disabilities. This article explores how a residential school addressed this gap. It provides details of how this need was met for seven students and the process undertaken to involve staff, parents and other stakeholders to establish ongoing support.

Diverse signalling by different chemokines through the chemokine receptor CCR5

We have investigated the signalling properties of the chemokine receptor, CCR5, using several assays for agonism: stimulation of changes in intracellular Ca(2+) or CCR5 internalisation in CHO cells expressing CCR5 or stimulation of [(35)S]GTPgammaS binding in membranes of CHO cells expressing CCR5. Four isoforms of the chemokine CCL3 with different amino termini (CCL3, CCL3(2-70), CCL3(5-70), CCL3L1) were tested in these assays in order to probe structure/activity relationships. Each isoform exhibited agonism. The pattern of agonism (potency, maximal effect) was different in the three assays, although the rank order was the same with CCL3L1 being the most potent and efficacious. The data show that the amino terminus of the chemokine is important for signalling. A proline at position 2 (CCL3L1) provides for high potency and efficacy but the isoform with a serine at position 2 (CCL3(2-70)) is as efficacious in some assays showing that the proline is not the only determinant of high efficacy. We also increased the sensitivity of CCR5 signalling by treating cells with sodium butyrate, thus increasing the receptor/G protein ratio. This allowed the detection of a change in intracellular Ca(2+) after treatment with CCL7 and Met-RANTES showing that these ligands possess measurable but low efficacy. This study therefore shows that sodium butyrate treatment increases the sensitivity of signalling assays and enables the detection of efficacy in ligands previously considered as antagonists. The use of different assay systems, therefore, provides different estimates of efficacy for some ligands at this receptor.