The 90-degree problem of scattering theory revisited: dynamical turbulence effects versus nonlinear effects

The 90° problem of cosmic-ray transport theory is revisited in this paper. By using standard forms of the wave spectrum in the solar wind, the pitch-angle Fokker–Planck coefficient and the parallel mean free path are computed for different resonance functions. A critical comparison is made of the strength of 90° scattering due to plasmawave effects, dynamical turbulence effects and nonlinear effects. It is demonstrated that, only for low-energy cosmic particles, dynamical effects are usually dominant. The novel results presented here are essential for an effective comparison of heliospheric observations for the parallel mean free path with the theoretical model results.

Determination of the degree of dissociation in an inductively coupled hydrogen plasma using optical emission spectroscopy and laser diagnostics

Gas temperature is of major importance in plasma based surface treatment, since the surface processes are strongly temperature sensitive. The spatial distribution of reactive species responsible for surface modification is also influenced by the gas temperature. Industrial applications of RF plasma reactors require a high degree of homogeneity of the plasma in contact with the substrate. Reliable measurements of spatially resolved gas temperatures are, therefore, of great importance. The gas temperature can be obtained, e.g. by optical emission spectroscopy (OES). Common methods of OES to obtain gas temperatures from analysis of rotational distributions in excited states do not include the population dynamics influenced by cascading processes from higher electronic states. A model was developed to evaluate this effect on the apparent rotational temperature that is observed. Phase resolved OES confirmed the validity of this model. It was found that cascading leads to higher apparent temperatures, but the deviation (~25 K) is relatively small and can be ignored in most cases. This analysis is applied to investigate axially and radially resolved temperature profiles in an inductively coupled hydrogen RF discharge.

An optimized method for the generation of AFLP markers in a stingless bee (Melipona quadrifasciata) reveals a high degree of intracolonial genetic polymorphism

This study describes an optimized protocol for the generation of Amplified Fragment Length Polymorphism (AFLP) markers in a stingless bee. Essential modifications to standard protocols are a restriction enzyme digestion (EcoRI and Tru1I) in a two-step procedure, combined with a touchdown program in the selective PCR amplification step and product labelling by incorporation of alpha[P-33]dATP. In an analysis of 75 workers collected from three colonies of Melipona quadrifasciata we obtained 719 markers. Analysis of genetic variability revealed that on average 32% of the markers were polymorphic within a colony. Compared to the overall percentage of polymorphism (44% of the markers detected in our bee samples), the observed rates of within-colony polymorphism are remarkably high, considering that the workers of each colony were all of spring of a singly mated queen.

Neuromuscular adaptation during skill acquisition on a two degree-of-freedom target-acquisition task: Isometric torque production

In this study we attempted to identify the principles that govern the changes in neural control that occur during repeated performance of a multiarticular coordination task. Eight participants produced isometric flexion/extension and pronation/supination torques at the radiohumeral joint, either in isolation (e.g., flexion) or in combination (e.g., flexion - supination), to acquire targets presented by a visual display. A cursor superimposed on the display provided feedback of the applied torques. During pre- and postpractice tests, the participants acquired targets in eight directions located either 3.6 cm (20% maximal voluntary contraction [MVC]) or 7.2 cm (40% MVC) from a neutral cursor position. On each of five consecutive days of practice the participants acquired targets located 5.4 cm (30% MVC) from the neutral position. EMG was recorded from eight muscles contributing to torque production about the radiohumeral joint during the pre- and posttests. Target-acquisition time decreased significantly with practice in most target directions and at both target torque levels. These performance improvements were primarily associated with increases in the peak rate of torque development after practice. At a muscular level, these changes were brought about by increases in the rates of recruitment of all agonist muscles. The spatiotemporal organization of muscle synergies was not significantly altered after practice. The observed adaptations appear to lead to performances that are generalizable to actions that require both greater and smaller joint torques than that practiced, and may be successfully recalled after a substantial period without practice. These results suggest that tasks in which performance is improved by increasing the rate of muscle activation, and thus the rate of joint torque development, may benefit in terms of the extent to which acquired levels of performance are maintained over time.

Neuromuscular adaptation during skill acquisition on a two degree-of-freedom target-acquisition task: Dynamic movement

In this experiment, we examined the extent to which the spatiotemporal reorganization of muscle synergies mediates skill acquisition on a two degree-of-freedom (df) target-acquisition task. Eight participants completed five practice sessions on consecutive days. During each session they practiced movements to eight target positions presented by a visual display. The movements required combinations of flexion/extension and pronation/supination of the elbow joint complex. During practice sessions, eight targets displaced 5.4 cm from the start position ( representing joint excursions of 54) were presented 16 times. During pre- and posttests, participants acquired the targets at two distances (3.6 cm [36 degrees] and 7.2 cm [72 degrees]). EMG data were recorded from eight muscles contributing to the movements during the pre- and posttests. Most targets were acquired more rapidly after the practice period. Performance improvements were, in most target directions, accompanied by increases in the smoothness of the movement trajectories. When target acquisition required movement in both dfs, there were also practice-related decreases in the extent to which the trajectories deviated from a direct path to the target. The contribution of monofunctional muscles ( those producing torque in a single df) increased with practice during movements in which they acted as agonists. The activity in bifunctional muscles ( those contributing torque in both dfs) remained at pretest levels in most movements. The results suggest that performance gains were mediated primarily by changes in the spatial organization of muscles synergies. These changes were expressed most prominently in terms of the magnitude of activation of the monofunctional muscles.

A New Concept of Interprofessional Education in Planning Programmes: Reflections on Healthy Urban Planning Project

Although widely debated, some of the defining professional characteristics of planners appear to be competencies in co-ordination, mediation and multidisciplinary working. Despite this, there is little pedagogical reflection on how interprofessional skills are promoted in planning programmes. This paper reflects on the experience of bringing together undergraduate students from medicine and planning to explore the concept of Healthy Urban Planning in a real life context of an urban motorway extension. This reveals a number of unexpected outcomes of such collaboration and points to the value of promoting interprofessional education, both as a way of increasing interest in some of the key challenges now facing society and in order to induce greater professional reflection amongst our students.

A New Concept of Interprofessional Education in Planning Programmes: Reflections on a Healthy Urban Planning Project

Although widely debated, some of the defining professional characteristics of planners appear to be competencies in co-ordination, mediation and multidisciplinary working. Despite this, there is little pedagogical reflection on how interprofessional skills are promoted in planning programmes. This paper reflects on the experience of bringing together undergraduate students from medicine and planning to explore the concept of Healthy Urban Planning in a real life context of an urban motorway extension. This reveals a number of unexpected outcomes of such collaboration and points to the value of promoting interprofessional education, both as a way of increasing interest in some of the key challenges now facing society and in order to induce greater professional reflection amongst students.

Recapitulation of embryological programmes in renal fibrosis - The importance of epithelial cell plasticity and developmental genes

Chronic fibrosis represents the final common pathway in progressive renal disease. Myofibroblasts deposit the constituents of renal scar, thus crippling renal function. It has recently emerged that an important source of these pivotal effector cells is the injured renal epithelium. This review concentrates on the process of epithelial-mesenchymal transition (EMT) and its regulation. The role of the developmental gene, gremlin, which is reactivated in adult renal disease, is the subject of particular focus. This member of the cysteine knot protein superfamily is critical to the process of nephrogenesis but quiescent in normal adult kidney. There is increasing evidence that gremlin expression reactivates in diabetic nephropathy, and in the diseased fibrotic kidney per se. Known to antagonize members of the bone morphogenic protein (BMP) family, gremlin may also act downstream of TGF-beta in induction of EMT. An increased understanding of the extracellular modulation of EMT and, in particular, of the gremlin-BMP axis may result in strategies that can halt or reverse the devastating progression of chronic renal fibrosis. Copyright (c) 2006 S. Karger AG, Basel.

Are rural development programmes socially inclusive? Social inclusion, civic engagement, participation, and social capital: Exploring the differences

Considerable importance is attached to social exclusion/inclusion in recent EU rural development programmes. At the national/regional operation of these programmes groups of people who are not participating are often identified as ‘socially excluded groups’. This article contends that rural development programmes are misinterpreting the social processes of participation and consequently labelling some groups as socially excluded when they are not. This is partly because of the interchangeable and confused use of the concepts social inclusion, social capital and civic engagement, and partly because of the presumption that to participate is the default position. Three groups identified as socially excluded groups in Northern Ireland are considered. It is argued that a more careful analysis of what social inclusion means, what civic engagement means, and why participation is presumed to be the norm, leads to a different conclusion about who is excluded. This has both theoretical and policy relevance for the much used concept of social inclusion.

Innovative Approaches to Involving Service Users in Palliative Care Social Work Education

Service user involvement in social work education is now a firmly established concept in UnitedKingdom.As a result, it is common practice for service users to occupy central roles the education and training of social work students and staff in both qualifying and postqualifying programmes. This paper describes an initiative, undertaken inNorthern Ireland, which compares two methods of user involvement employed with undergraduate and postqualifying social work students. In both situations the students firstly observed discussedDVDexcerpts of narratives from people affected by cancer and secondly observed live facilitated interview with a 25-year-old male service user who shared his experiences being diagnosedwith cancer at a young age.Understanding the social work role in palliative care is crucial as all social workers, regardless of practice context, will have some degree involvement in helping individuals and families to address end-of-life care issues. paper compares the findings of evaluations from two student groups which may help inform social work educators about the effectiveness of different teaching methods used achieve meaningful and effective user involvement with seldom heard groups.