Protein engineering of subtilisin BPN'

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Experiments in the automatic marking of ER-Diagrams

In this paper we present an approach to the computer understanding of diagrams and show how it can be successfully applied to the automatic marking (grading) of student attempts at drawing entity-relationship (ER) diagrams. The automatic marker has been incorporated into a revision tool to enable students to practice diagramming and obtain feedback on their attempts

Using patterns in the automatic marking of ER-Diagrams

This paper illustrates how the notion of pattern can be used in the automatic analysis and synthesis of diagrams, applied particularly to the automatic marking of ER-diagrams. The paper describes how diagram patterns fit into a general framework for diagram interpretation and provides examples of how patterns can be exploited in other fields. Diagram patterns are defined and specified within the area of ER-diagrams. The paper also shows how patterns are being exploited in a revision tool for understanding ER-diagrams

Modelling the impacts of the industrial biofuels strategy on the South African agricultural and biofuel subsectors

The potential impact of the current South African industrial biofuels strategy on the economic feasibility of biofuel production in South Africa is analysed and discussed. The analysis is then taken a step further by means of a scenario to analyse the potential impacts of higher global prices on the feasibility of a local biofuel industry. The BFAP sector model, a partial equilibrium model, is used to simulate the various impacts over the period 2009 to 2017. This study shows that the incentives and commitments, as presented through the strategy, are not sufficient to get a local biofuel industry up and running and make it sustainable in the long term.Resource /Energy Economics and Policy,

Modelling the impacts of macro-economic variables on the South African biofuels industry

The production of biofuels from agricultural commodities has received much attention in recent years. Apart from a few private initiatives, biofuels have not seen a large scale, commercial production in South Africa to date. This article sketches a basic picture of the economic feasibility of biofuel production in South Africa, without any form of government support, at 2006 prices. It then takes the analysis a step further and with the aid of a set of scenarios, different potential outcomes, due to a range of possible policy implementation measures, are discussed and the results documented. The Bureau for Food and Agricultural Policy’s (BFAP) sector model is used to simulate the impact of various options on the potential biofuels industry and other related industries during the course of the 2007 to 2015 period. This study shows that a lack of government support for the local biofuels industry could seriously affect its economic viability, especially in the early stages of the industry’s development. Additional issues, such as the impact on food and feed prices, also need to be taken into consideration.Resource /Energy Economics and Policy,

Automated ice-core layer-counting with strong univariate signals

We present an automated process for determining the annual layer chronology of an ice-core with a strong annual signal, utilising the hydrogen peroxide record from an Antarctic Peninsula ice-core as a test signal on which to count annual cycles and explain the methods. The signal is de-trended and normalised before being split into sections with a deterministic cycle count and those that need more attention. Possible reconstructions for the uncertain sections are determined which could be used as a visual aid for manual counting, and a simple method for assigning probability measures to each reconstruction is discussed. The robustness of this process is explored by applying it to versions of two different chemistry signals from the same stretch of the NGRIP (North Greenland Ice Core Project) ice-core, which shows more variation in annual layer thickness, with and without thinning to mimic poorer quality data. An adapted version of these methods is applied to the more challenging non-sea-salt sulphur signal from the same Antarctic Peninsula core from which the hydrogen peroxide signal was taken. These methods could readily be adapted for use on much longer datasets, thereby reducing manual effort and providing a robust automated layer-counting methodology

Resting respiratory tract dendritic cells preferentially stimulate T helper cell Type 2(Th2) responses and require obligatory cytokine signals for induction of Th1 immunity

Consistent with their role in host defense, mature dendritic cells (DCs) from central lymphoid organs preferentially prime for T helper cell type 1 (Th1)-polarized immunity. However, the “default” T helper response at mucosal surfaces demonstrates Th2 polarity, which is reflected in the cytokine profiles of activated T cells from mucosal lymph nodes. This study on rat respiratory tract DCs (RTDCs) provides an explanation for this paradox. We demonstrate that freshly isolated RTDCs are functionally immature as defined in vitro, being surface major histocompatibility complex (MHC) II lo, endocytosishi, and mixed lymphocyte reactionlo, and these cells produce mRNA encoding interleukin (IL)-10. After ovalbumin (OVA)-pulsing and adoptive transfer, freshly isolated RTDCs preferentially stimulated Th2-dependent OVA-specific immunoglobulin (Ig)G1 responses, and antigen-stimulated splenocytes from recipient animals produced IL-4 in vitro. However, preculture with granulocyte/macrophage colony stimulating factor increased their in vivo IgG priming capacity by 2–3 logs, inducing production of both Th1- and Th2-dependent IgG subclasses and high levels of IFN-γ by antigen-stimulated splenocytes. Associated phenotypic changes included upregulation of surface MHC II and B7 expression and IL-12 p35 mRNA, and downregulation of endocytosis, MHC II processing– associated genes, and IL-10 mRNA expression. Full expression of IL-12 p40 required additional signals, such as tumor necrosis factor α or CD40 ligand. These results suggest that the observed Th2 polarity of the resting mucosal immune system may be an inherent property of the resident DC population, and furthermore that mobilization of Th1 immunity relies absolutely on the provision of appropriate microenvironmental costimuli

Idealized Multigrid Algorithm for Staggered Fermions

An idealized multigrid algorithm for the computation of propagators of staggered fermions is investigated. Exemplified in four-dimensional $SU(2)$ gauge fields, it is shown that the idealized algorithm preserves criticality under coarsening. The same is not true when the coarse grid operator is defined by the Galerkin prescription. Relaxation times in computations of propagators are small, and critical slowing is strongly reduced (or eliminated) in the idealized algorithm. Unfortunately, this algorithm is not practical for production runs, but the investigations presented here answer important questions of principle.Comment: 11 pages, no figures, DESY 93-046; can be formatted with plain LaTeX article styl

Shared Care, Elder and Family Member Skills Used to Manage Burden

Aim. The aim of this paper is to further develop the construct of Shared Care by comparing and contrasting it to related research, and to show how the construct can be used to guide research and practice. Background. While researchers have identified negative outcomes for family caregivers caused by providing care, less is known about positive aspects of family care for both members of a family dyad. Understanding family care relationships is important to nurses because family participation in the care of chronically ill elders is necessary to achieve optimal outcomes from nursing interventions. A previous naturalistic inquiry identified a new construct, Shared Care, which was used to describe a family care interaction that contributed to positive care outcomes. Methods. A literature review was carried out using the databases Medline, CINAHL, and Psych-info and the keywords home care, care receiver, disability, family, communication, decision-making and reciprocity. The results of the review were integrated to suggest how Shared Care could be used to study care difficulties and guide interventions. Results. The literature confirmed the importance of dyad relationships in family care. Shared Care extended previous conceptualizations of family care by capturing three critical components: communication, decision-making, and reciprocity. Shared Care provides a structure to expand the conceptualization of family care to include both members of a care dyad and account for positive and negative aspects of care. Conclusions. The extended view provided by the construct of Shared Care offers practitioners and scholars tools to use in the context of our ageing population to improve the effectiveness of family care relationships