Patterns of peristome reduction and ornamentation in African Entodontaceae

The Entodontaceae is characterised by erect capsules with inset and substantially reduced peristomes. Differences in peristome morphology and ornamentation delimit both genera and species within the family. The Entodontaceae, as presently recognised, consists of four genera, Entodon, Erythrodontium, Mesonodon and Pylaisiobryum, which show a variety of peristome ornamentation patterns, and exhibit differing levels of peristome reduction. This variation encompasses an unusual combination of structurally reduced peristomes, which retain massive exostome ornamentation, and residual peristome function. As part of a taxonomic revision of the family in Africa, generic patterns of peristome reduction and ornamentation are described. Inter- and intra-specific variation patterns of both the exostome and endostome have been investigated using detailed SEM studies of material from Africa and beyond. Structural reduction of the peristome is associated with high levels of intra-specific variation in peristome ornamentation patterns. Common trends in these patterns of variation are identified within the family. Putative hybrid sporophytes have been identified in Entodon, and the taxonomic implications of these observations are considered for a family where species delimitation has in the past often depended on minor variation in peristome structure or ornamentation patterns. (author abst.)

The impact of ICT on the work patterns of managers and their organisations

Purpose – The main aim of this paper is to present the results of a study examining managers' attitudes towards the deployment and use of information and communications technology (ICT) in their organisations. The study comes at a time when ICT is being recognised as a major enabler of innovation and new business models, which have the potential to have major impact on western economies and jobs. Design/methodology/approach – A questionnaire was specially designed to collect data relating to three research questions. The questionnaire also included a number of open-ended questions. A total of 181 managers from a wide range of industries across a number of countries participated in the electronic survey. The quantitative responses to the survey were analysed using SPSS. Exploratory factor analysis using Varimax rotation was used and ANOVA to compare responses by different groups. Findings – The survey showed that many of the respondents appeared equipped to work “any place, any time”. However, it also highlighted the challenges managers face in working in a connected operation. Also, the data suggested that many managers were less than confident about their companies' policies and practices in relation to information management. Originality/value – A next step from this exploratory research could be the development of a model exploring the impact of ICT on management and organisational performance in terms of personal characteristics of the manager, the role performed, the context and the ICT provision. Also, further research could focus on examining in more detail differences between management levels.

Perceptual grouping ability in Williams syndrome: evidence for deviant patterns of performance

Williams syndrome (WS) is a rare genetic disorder. At a cognitive level, this population display poor visuo-spatial cognition when compared to verbal ability. Within the visuo-spatial domain, it is now accepted that individuals with WS are able to perceive both local and global aspects of an image, albeit at a low level. The present study examines the manner in which local elements are grouped into a global whole in WS. Fifteen individuals with WS and 15 typically developing controls, matched for non-verbal ability, were presented with a matrix of local elements and asked whether these elements were perceptually grouped horizontally or vertically. The WS group was at the same level as the control group when grouping by luminance, closure, and alignment. However, their ability to group by shape, orientation and proximity was significantly poorer than controls. This unusual profile of grouping abilities in WS suggests that these individuals do not form a global percept in a typical manner. (c) 2004 Published by Elsevier Ltd.

Changing patterns of cognitive-motor interference (CMI) over time during recovery from stroke

Objective: To explore the extent and nature of change in cognitive-motor interference (CMI) among rehabilitating stroke patients who showed dual-task gait decrement at initial assessment. Design: Experimental, with in-subjects, repeated measures design. Setting: Rehabilitation centre for adults with acquired, nonprogressive brain injury. Subjects: Ten patients with unilateral stroke, available for reassessment 1-9 months following their participation in a study of CMI after brain injury. Measures: Median stride duration; mean word generation. Methods: Two x one-minute walking trials, two x one-minute word generation trials, two x one-minute trials of simultaneous walking and word generation; 10-metre walking time; Barthel ADL Scale score. Results: Seven out of ten patients showed reduction over time in dual-task gait decrement. Three out of ten showed reduction in cognitive decrement. Only one showed concomitant reduction in gait and word generation decrement. Conclusion: Extent of CMI during relearning to walk after a stroke reduced over time in the majority of patients. Effects were more evident in improved stride duration than improved cognitive performance. Measures of multiple task performance should be included in assessment for functional recovery.

Recent patterns of change in vegetation structure and tree composition of British broadleaved woodland: evidence from large-scale surveys

Evidence is presented of widespread changes in structure and species composition between the 1980s and 2003–2004 from surveys of 249 British broadleaved woodlands. Structural components examined include canopy cover, vertical vegetation profiles, field-layer cover and deadwood abundance. Woods were located in 13 geographical localities and the patterns of change were examined for each locality as well as across all woods. Changes were not uniform throughout the localities; overall, there were significant decreases in canopy cover and increases in sub-canopy (2–10 m) cover. Changes in 0.5–2 m vegetation cover showed strong geographic patterns, increasing in western localities, but declining or showing no change in eastern localities. There were significant increases in canopy ash Fraxinus excelsior and decreases in oak Quercus robur/petraea. Shrub layer ash and honeysuckle Lonicera periclymenum increased while birch Betula spp. hawthorn Crataegus monogyna and hazel Corylus avellana declined. Within the field layer, both bracken Pteridium aquilinum and herbs increased. Overall, deadwood generally increased. Changes were consistent with reductions in active woodland management and changes in grazing and browsing pressure. These findings have important implications for sustainable active management of British broadleaved woodlands to meet silvicultural and biodiversity objectives.

Equine anthelmintics: survey of the patterns of use, beliefs and attitudes among horse owners in the UK

An online survey was conducted to establish horse owners' beliefs, attitudes and practices relating to the use of anthelmintic drugs. Out of a total of 574 respondents, 89 per cent described themselves as ‘leisure riders’, most of whom took part in a variety of activities including eventing, show jumping, dressage, hunter trials, hunting, driving, endurance and showing. Overall, respondents were generally aware and concerned about the issue of anthelmintic resistance. Less than 60 per cent of all respondents were comfortable with their existing anthelmintic programme, and 25 per cent would like to reduce the use of anthelmintics in their horses. Of all the respondents, 47 per cent used livery, and 49 per cent of those reported that the livery imposed a common anthelmintic programme for horses kept on the premises; 45 per cent of these respondents were not entirely happy with the livery yard's programme. Less than 50 per cent of all respondents included ‘veterinary surgeon’ among their sources of advice on worming.

Patterns of nucleotide substitution in angiosperm cpDNA trnL (UAA)-trnF (GAA) regions

Patterns of substitution in chloroplast encoded trnL_F regions were compared between species of Actaea (Ranunculales), Digitalis (Scrophulariales), Drosera (Caryophyllales), Panicoideae (Poales), the small chromosome species clade of Pelargonium (Geraniales), each representing a different order of flowering plants, and Huperzia (Lycopodiales). In total, the study included 265 taxa, each with > 900-bp sequences, totaling 0.24 Mb. Both pairwise and phylogeny-based comparisons were used to assess nucleotide substitution patterns. In all six groups, we found that transition/transversion ratios, as estimated by maximum likelihood on most-parsimonious trees, ranged between 0.8 and 1.0 for ingroups. These values occurred both at low sequence divergences, where substitutional saturation, i.e., multiple substitutions having occurred at the same (homologous) nucleotide position, was not expected, and at higher levels of divergence. This suggests that the angiosperm trnL-F regions evolve in a pattern different from that generally observed for nuclear and animal mtDNA (transitional/transversion ratio > or = 2). Transition/transversion ratios in the intron and the spacer region differed in all alignments compared, yet base compositions between the regions were highly similar in all six groups. A>-C transversions were significantly less frequent than the other four substitution types. This correlates with results from studies on fidelity mechanisms in DNA replication that predict A<->T and G<->C transversions to be least likely to occur. It therefore strengthens confidence in the link between mutation bias at the polymerase level and the actual fixation of substitutions as recorded on evolutionary trees, and concomitantly, in the neutrality of nucleotide substitutions as phylogenetic markers.