Communities of practice in UK large contracting firms: contrasting application and non-utilized merits

The idea of a community of practice (CoP) has been offered as the engine to unlock the potential of organizational resources, mainly knowledge and people, to achieve the strategic goal of sustained competitiveness. The relevance and application of CoPs in large UK contracting companies was investigated using two case studies. Contrasting variations in the understanding of the concept between the two contracting companies were observed. While a CoP was applied in one company with strategic intent, the concept was not fully understood in the other. In one company, only a third of CoP members surveyed agreed that CoPs were a vehicle for driving best practice and innovation throughout the business; this compared with more than 60% in agreement in the other contracting firm. The higher agreement and satisfaction of CoP members in the latter case study was the result of the management's understanding and commitment. CoPs require time and organizational support to mature. The strategic inception and management support of CoP application is vital for their maturation and progress. Although the construction industry change discourses portray CoPs as fostering an environment of trust, and hence serving as innovation and competiveness enablers, their potential contribution to contracting firms does not provide a compelling case and hence merits further research studies.

Distribution of esterase activity in porcine ear skin, and the effects of freezing and heat separation

Porcine ear skin is widely used to study skin permeation and absorption of ester compounds, whose permeation and absorption profiles may be directly influenced by in situ skin esterase activity. Importantly, esterase distribution and activity in porcine ear skin following common protocols of skin handling and storage have not been characterised. Thus, we have compared the distribution and hydrolytic activity of esterases in freshly excised, frozen, heated and explanted porcine ear skin. Using an esterase staining kit, esterase activity was found to be localised in the stratum corneum and viable epidermis. Under frozen storage and a common heating protocol of epidermal sheet separation, esterase staining in the skin visibly diminished. This was confirmed by a quantitative assay using HPLC to monitor the hydrolysis of aspirin, in freshly excised, frozen or heated porcine ear skin. Compared to vehicle-only control, the rate of aspirin hydrolysis was approximately three-fold higher in the presence of freshly excised skin, but no different in the presence of frozen or heated skin. Therefore, frozen and heat-separated porcine ear skin should not be used to study the permeation of ester-containing permeants, in particular co-drugs and pro-drugs, whose hydrolysis or degradation can be modulated by skin esterases.

Causal evidence for frontal involvement in memory target maintenance by posterior brain areas during distracter interference of visual working memory

Dorsolateral prefrontal cortex (DLPFC) is recruited during visual working memory (WM) when relevant information must be maintained in the presence of distracting information. The mechanism by which DLPFC might ensure successful maintenance of the contents of WM is, however, unclear; it might enhance neural maintenance of memory targets or suppress processing of distracters. To adjudicate between these possibilities, we applied time-locked transcranial magnetic stimulation (TMS) during functional MRI, an approach that permits causal assessment of a stimulated brain region's influence on connected brain regions, and evaluated how this influence may change under different task conditions. Participants performed a visual WM task requiring retention of visual stimuli (faces or houses) across a delay during which visual distracters could be present or absent. When distracters were present, they were always from the opposite stimulus category, so that targets and distracters were represented in distinct posterior cortical areas. We then measured whether DLPFC-TMS, administered in the delay at the time point when distracters could appear, would modulate posterior regions representing memory targets or distracters. We found that DLPFC-TMS influenced posterior areas only when distracters were present and, critically, that this influence consisted of increased activity in regions representing the current memory targets. DLPFC-TMS did not affect regions representing current distracters. These results provide a new line of causal evidence for a top-down DLPFC-based control mechanism that promotes successful maintenance of relevant information in WM in the presence of distraction.

Analyzing the meaning of background speech is obligatory, distraction by meaning is not

The effects of background English and Welsh speech on memory for visually-presented English words were contrasted amongst monolingual English speakers and bilingual Welsh-English speakers. Equivalent disruption to the English language task was observed amongst Welsh-speaking bilinguals from both English and Welsh speech, but English-speaking monolinguals displayed less disruption from the Welsh speech. An effect of the meaning of the background speech was therefore apparent amongst bilinguals even when the focal memory task was presented in a different language from the distracting speech. A second experiment tested only English-speaking monolinguals, using English as background speech, but varied the demands of the focal task. Participants were asked either to count the number of vowels in words visually presented for future recall, or to rate them for pleasantness, before subsequently being asked to recall the words. Greater disruption to recall was observed from meaningful background speech when participants initially rated the words for pleasantness than when they initially counted the vowels within the words. These results show that background speech is automatically analyzed for meaning, but whether the meaning of the background speech causes distraction is critically dependent upon the nature of the focal task. The data underscore the need to consider not only the nature of office noise, but also the demands and content of the work task when assessing the effects of office noise on work performance.

Role of lipids in human nutrition

Fat is a major contributor to energy intake in most Western diets, supplying 35–40% of food energy. It is described as being ‘energy-dense’, because a gram of fat (9 kcal/g) yields more than twice as much metabolisable energy as a gram of either carbohydrate or protein (4 kcal/g). Most of the fat we consume in our diet is in the form of triacylglycerol (90-95%), with cholesterol and phospholipids making up the bulk of the remainder. Dietary advice invariably stresses the importance of fat reduction, yet fats have diverse roles in human nutrition. They are important as a source of energy, both for immediate utilisation by the body and in laying down a storage depot (adipose tissue) for later utilisation when food intake is reduced, they act as a vehicle for the ingestion and absorption of fat-soluble vitamins, and they have diverse structural and functional roles in the body. Cholesterol is also an essential component of cell membranes and is the precursor for synthesis of hormones. This chapter describes the structure, digestion, transport and functional properties of dietary fat in the body and explains the basis of associations between fat consumption and chronic disease.

Lexical access across languages: a multinomial model of auditory distraction

Recall in many types of verbal memory task is reliably disrupted by the presence of auditory distracters, with verbal distracters frequently proving the most disruptive (Beaman, 2005). A multinomial processing tree model (Schweickert, 1993) is applied to the effects on free recall of background speech from a known or an unknown language. The model reproduces the free recall curve and the impact on memory of verbal distracters for which a lexical entry exists (i.e., verbal items from a known language). The effects of semantic relatedness of distracters within a language is found to depend upon a redintegrative factor thought to reflect the contribution of the speech-production system. The differential impacts of known and unknown languages cannot be accounted for in this way, but the same effects of distraction are observed amongst bilinguals, regardless of distracter-language.

Built environment research in West Africa: current trends and future directions

The countries in West Africa (WA) are pushing for socio-economic development. The construction sector has an important part to play in helping to realise these aspirations. This necessitates an increased emphasis on research in the built environment, as a key contributor to developing capacity, knowledge and technologies for the sector. The West Africa Built Environment Research (WABER) conference was initiated in 2008. The objective was to: help young built environment researchers in West Africa (WA) to develop their research work and skills through constructive face-to-face interaction with their peers and experienced international academics; supply a platform for interaction among more senior academics and an outlet for disseminating their research work; and to serve as a vehicle for developing the built environment field in Africa. Three conferences have so far been organised, 2009 - 2011, bringing together ~300 academics, researchers and practitioners from the WA region. This paper draws on content analysis of the 189 papers in the proceedings of three conferences: 2009 (25); 2010 (57) and 2011 (107). These papers provide a window into current research priorities and trends and, thus, offer an opportunity to understand the kinds of research work undertaken by built environment researchers in West Africa. The aim is to illuminate the main research themes and methods that are currently pursued and the limitations thereof. The findings lay bare some of the many challenges that are faced by academics in WA and provide suggestions for alternative directions for future research and development work with indications of a potential research agenda.

The "Fair trade nation": market-oriented development in devolved European regions

Scholars have largely ignored the roles played by government and public sector institutions in the fair trade movement. This article addresses the knowledge gap through examining government involvement in fair trade networks in the context of European devolution and the localization of international development action. Proposing a relational view of fair trade networks, and considering the Fair Trade Nation as a social category for development, it highlights how power sources outside the centralized nation-state permit a political community to associate itself with fair trade. Research from Wales demonstrates that government acts in a leadership role rather than as regulator, conferring political voice and finance while enhancing its international credentials and contributing to the politics of nation-building. Our conclusion is cautious; campaigners celebrate political commitment to fair trade embodied within the category of the Fair Trade Nation, but evidence suggests that government reliance on the market as a vehicle for decentralized development action is limited by how the Fair Trade Nation is currently executed.

Auditory distraction eliminates retrieval induced forgetting: implications for the processing of unattended sound

The Retrieval-Induced Forgetting (RIF) paradigm includes three phases: (a) study/encoding of category exemplars, (b) practicing retrieval of a sub-set of those category exemplars, and (c) recall of all exemplars. At the final recall phase, recall of items that belong to the same categories as those items that undergo retrieval-practice, but that do not undergo retrieval-practice, is impaired. The received view is that this is because retrieval of target category-exemplars (e.g., ‘Tiger’ in the category Four-legged animal) requires inhibition of non-target category-exemplars (e.g., ‘Dog’ and ‘Lion’) that compete for retrieval. Here, we used the RIF paradigm to investigate whether ignoring auditory items during the retrieval-practice phase modulates the inhibitory process. In two experiments, RIF was present when retrieval-practice was conducted in quiet and when conducted in the presence of spoken words that belonged to a category other than that of the items that were targets for retrieval-practice. In contrast, RIF was abolished when words that either were identical to the retrieval-practice words or were only semantically related to the retrieval-practice words were presented as background speech. The results suggest that the act of ignoring speech can reduce inhibition of the non-practiced category-exemplars, thereby eliminating RIF, but only when the spoken words are competitors for retrieval (i.e., belong to the same semantic category as the to-be-retrieved items).

Multi-vehicle planning using RRT-connect

The problem of planning multiple vehicles deals with the design of an effective algorithm that can cause multiple autonomous vehicles on the road to communicate and generate a collaborative optimal travel plan. Our modelling of the problem considers vehicles to vary greatly in terms of both size and speed, which makes it suboptimal to have a faster vehicle follow a slower vehicle or for vehicles to drive with predefined speed lanes. It is essential to have a fast planning algorithm whilst still being probabilistically complete. The Rapidly Exploring Random Trees (RRT) algorithm developed and reported on here uses a problem specific coordination axis, a local optimization algorithm, priority based coordination, and a module for deciding travel speeds. Vehicles are assumed to remain in their current relative position laterally on the road unless otherwise instructed. Experimental results presented here show regular driving behaviours, namely vehicle following, overtaking, and complex obstacle avoidance. The ability to showcase complex behaviours in the absence of speed lanes is characteristic of the solution developed.

Multi-level planning for semi-autonomous vehicles in traffic scenarios based on separation maximization

The planning of semi-autonomous vehicles in traffic scenarios is a relatively new problem that contributes towards the goal of making road travel by vehicles free of human drivers. An algorithm needs to ensure optimal real time planning of multiple vehicles (moving in either direction along a road), in the presence of a complex obstacle network. Unlike other approaches, here we assume that speed lanes are not present and that different lanes do not need to be maintained for inbound and outbound traffic. Our basic hypothesis is to carry forward the planning task to ensure that a sufficient distance is maintained by each vehicle from all other vehicles, obstacles and road boundaries. We present here a 4-layer planning algorithm that consists of road selection (for selecting the individual roads of traversal to reach the goal), pathway selection (a strategy to avoid and/or overtake obstacles, road diversions and other blockages), pathway distribution (to select the position of a vehicle at every instance of time in a pathway), and trajectory generation (for generating a curve, smooth enough, to allow for the maximum possible speed). Cooperation between vehicles is handled separately at the different levels, the aim being to maximize the separation between vehicles. Simulated results exhibit behaviours of smooth, efficient and safe driving of vehicles in multiple scenarios; along with typical vehicle behaviours including following and overtaking.

Planning autonomous vehicles in the absence of speed lanes using lateral potentials

Chaotic traffic, prevalent in many countries, is marked by a large number of vehicles driving with different speeds without following any predefined speed lanes. Such traffic rules out using any planning algorithm for these vehicles which is based upon the maintenance of speed lanes and lane changes. The absence of speed lanes may imply more bandwidth and easier overtaking in cases where vehicles vary considerably in both their size and speed. Inspired by the performance of artificial potential fields in the planning of mobile robots, we propose here lateral potentials as measures to enable vehicles to decide about their lateral positions on the road. Each vehicle is subjected to a potential from obstacles and vehicles in front, road boundaries, obstacles and vehicles to the side and higher speed vehicles to the rear. All these potentials are lateral and only govern steering the vehicle. A speed control mechanism is also used for longitudinal control of vehicle. The proposed system is shown to perform well for obstacle avoidance, vehicle following and overtaking behaviors.

Memory as discrimination: what distraction reveals

Recalling information involves the process of discriminating between relevant and irrelevant information stored in memory. Not infrequently, the relevant information needs to be selected from amongst a series of related possibilities. This is likely to be particularly problematic when the irrelevant possibilities are not only temporally or contextually appropriate but also overlap semantically with the target or targets. Here, we investigate the extent to which purely perceptual features which discriminate between irrelevant and target material can be used to overcome the negative impact of contextual and semantic relatedness. Adopting a distraction paradigm, it is demonstrated that when distracters are interleaved with targets presented either visually (Experiment 1) or auditorily (Experiment 2), a within-modality semantic distraction effect occurs; semantically-related distracters impact upon recall more than unrelated distracters. In the semantically-related condition, the number of intrusions in recall is reduced whilst the number of correctly recalled targets is simultaneously increased by the presence of perceptual cues to relevance (color features in Experiment 1 or speaker’s gender in Experiment 2). However, as demonstrated in Experiment 3, even presenting semantically-related distracters in a language and a sensory modality (spoken Welsh) distinct from that of the targets (visual English) is insufficient to eliminate false recalls completely, or to restore correct recall to levels seen with unrelated distracters . Together, the study shows how semantic and non-semantic discriminability shape patterns of both erroneous and correct recall.

Planning autonomous vehicles in the absence of speed lanes using an elastic strip

Planning of autonomous vehicles in the absence of speed lanes is a less-researched problem. However, it is an important step toward extending the possibility of autonomous vehicles to countries where speed lanes are not followed. The advantages of having nonlane-oriented traffic include larger traffic bandwidth and more overtaking, which are features that are highlighted when vehicles vary in terms of speed and size. In the most general case, the road would be filled with a complex grid of static obstacles and vehicles of varying speeds. The optimal travel plan consists of a set of maneuvers that enables a vehicle to avoid obstacles and to overtake vehicles in an optimal manner and, in turn, enable other vehicles to overtake. The desired characteristics of this planning scenario include near completeness and near optimality in real time with an unstructured environment, with vehicles essentially displaying a high degree of cooperation and enabling every possible(safe) overtaking procedure to be completed as soon as possible. Challenges addressed in this paper include a (fast) method for initial path generation using an elastic strip, (re-)defining the notion of completeness specific to the problem, and inducing the notion of cooperation in the elastic strip. Using this approach, vehicular behaviors of overtaking, cooperation, vehicle following,obstacle avoidance, etc., are demonstrated.

Modelling the economics of farm-based anaerobic digestion in a UK whole-farm context

Anaerobic digestion (AD) technologies convert organic wastes and crops into methane-rich biogas for heating, electricity generation and vehicle fuel. Farm-based AD has proliferated in some EU countries, driven by favourable policies promoting sustainable energy generation and GHG mitigation. Despite increased state support there are still few AD plants on UK farms leading to a lack of normative data on viability of AD in the whole-farm context. Farmers and lenders are therefore reluctant to fund AD projects and policy makers are hampered in their attempts to design policies that adequately support the industry. Existing AD studies and modelling tools do not adequately capture the farm context within which AD interacts. This paper demonstrates a whole-farm, optimisation modelling approach to assess the viability of AD in a more holistic way, accounting for such issues as: AD scale, synergies and conflicts with other farm enterprises, choice of feedstocks, digestate use and impact on farm Net Margin. This modelling approach demonstrates, for example, that: AD is complementary to dairy enterprises, but competes with arable enterprises for farm resources. Reduced nutrient purchases significantly improve Net Margin on arable farms, but AD scale is constrained by the capacity of farmland to absorb nutrients in AD digestate.