790 research outputs found
Integrated specifications for abstract systems
Journal ArticleStructural specifications define an abstract object as a composition of other abstract objects. Behavioral specifications define an abstract object in terms of its associated operations. Integrated specifications are a combination of structural and behavioral specifications which are more powerful than either used alone. By providing four naming mechanisms, integrated specifications hide the details of how objects are represented and accessed on storage devices. The four naming mechanisms allow objects to be named in terms of the operations previously applied to them, the unique attributes they possess, the relationships they participate in, and the categories they belong to. Integrated specifications can specify the structure of more abstract systems than the relational database model, while also characterizing dynamic properties. Examples are given of integrated specifications for quide, symboltable and expression. These specifications are simple and guide, but do not constrain, the implementor in designing refinements. By exploiting abstract structure in specifications, common aspects of inter-object communication can be suppressed and only salient differences emphasized. Integrated specifications can make a significant contribution to the useability, reliability and efficiency of computer systems
Using Geological Facies to Estimate Chromate Sorption to Soils
Quantifying the extent to which contaminant metals bind to subsurface soils is important for risk assessment, the tendency for a contaminant to migrate, and developing environmental remediation strategies. Unfortunately, subsurface soils vary widely in their composition, which in turn affect their tendency to bind metals. The hypothesis of this study was predicated on how a better understanding of geological facies would reduce uncertainty associated with predicting contaminant metal sorption. Facies are layers of sediment deposited in the subsurface due to similar depositional conditions, including energy of an overlying waterway. As such, facies are expected to have similar assemblages of minerals, particle size distributions, origins of organic matter, and similar microbial population structures. These are all important factors affecting contaminant metal sorption. The approach of this study was to collect 42 composite soil samples from a 5 m by 1.5 m grid outcrop in Graniteville, South Carolina and five end-member facies samples. The fraction of each of the five facies comprising the 42 composite soil samples were estimated. Particle size distribution (gravel, sand, silt, and clay fractions), pH, organic matter (OM), iron coating content, and microbial colony forming units were determined for each composite soil and the five end-member facies soils. Because hexavalent chromium (Cr) is the most common contaminant metal in the U.S. to exceed drinking water limits, this highly toxic and soluble metal was used as a model contaminant to provide a measure of contaminant sorption. Chromium distribution coefficients (Kd = Crsoil/Crwater) were measured. Significant correlations were identified between several soil chemical and microbial properties. A significant correlation (r = 0.423; p ≤ 0.05, d.f. = 47) was also determined between measured Kd values and Kd values calculated based on knowledge of facies Kd values. Importantly, the calculated values were characterized by large amount of inherent error. Additional work is needed to determine the applicability of this approach for remediation of contaminated sites and how best to identify appropriate facies for this novel application
Implications of antimicrobial combinations in complex wound biofilms containing fungi
Diabetic foot ulcer treatment currently focuses on targeting bacterial biofilms, while dismissing fungi. To investigate this we used an in vitro biofilm model containing bacteria and fungi, reflective of the wound environment, to test the impact of antimicrobials. Here we showed that while mono-treatment approaches influenced biofilm composition it had no discernible effect on overall quantity. Only by combining bacterial and fungal specific antibiotics were we able to decrease the biofilm bioburden, irrespective of composition
Judicial Review, Irrationality, and the Legitimacy of Merits-Review
The definition of the irrationality ground of judicial review recognises the constitutional principle of the separation of powers, in allowing for judicial control of the executive only very rarely. The author in a previous article in this study found that the courts, on occasions, had intervened in circumstances where administrative decisions arguably were not irrational. To this end, the purpose of this article is to assess the constitutionality of these seemingly low standards of irrationality. The author does so by reference either to the manner of review employed—the use of the proportionality principle, for example—or the context of the administrative decision under scrutiny, such as the infringement of the applicant’s fundamental rights. The author finds that the cases from the previous article where low standards of irrationality were arguably adopted were, in fact, legitimate according to these chosen methods of evaluation. However, this is an interim conclusion because, for reasons of word length, the author is unable to complete a full assessment here. It is therefore proposed that a subsequent article will continue to examine the constitutionality of these cases. Furthermore, the author will also try and establish a zone of executive decision-making, for reasons of democracy, where the courts are excluded from irrationality review. If the author is unsuccessful in this regard, the final conclusion of this study will inevitably be that low standards of judicial intervention exist without limit—a clear assault on the constitutional principle stated above
Anomalies in T cell function are associated with individuals at risk of mycobacterium abscessus complex infection
The increasing global incidence and prevalence of non-tuberculous mycobacteria (NTM) infection is of growing concern. New evidence of person-to-person transmission of multidrug-resistant NTM adds to the global concern. The reason why certain individuals are at risk of NTM infections is unknown. Using high definition flow cytometry, we studied the immune profiles of two groups that are at risk of Mycobacterium abscessus complex infection and matched controls. The first group was cystic fibrosis (CF) patients and the second group was elderly individuals. CF individuals with active M. abscessus complex infection or a history of M. abscessus complex infection exhibited a unique surface T cell phenotype with a marked global deficiency in TNFa production during mitogen stimulation. Importantly, immune-based signatures were identified that appeared to predict at baseline the subset of CF individuals who were at risk of M. abscessus complex infection. In contrast, elderly individuals with M. abscessus complex infection exhibited a separate T cell phenotype underlined by the presence of exhaustion markers and dysregulation in type 1 cytokine release during mitogen stimulation. Collectively, these data suggest an association between T cell signatures and individuals at risk of M. abscessus complex infection, however, validation of these immune anomalies as robust biomarkers will require analysis on larger patient cohorts
Improving Together: A National Framework for Quality and GP Clusters in Scotland
Improving together will complement the development of the Scottish national GP contract that sets out the role of GPs and their important contribution as clinical leaders and expert medical generalists working in a community setting. This framework will be reviewed by the Scottish Government and the Scottish General Practitioners Committee of the BMA on a periodic basis, attentive to feedback from those involved in delivering its intent. As such, it is a framework that will develop to its full potential over time, as elements of the transformation of primary care in Scotland create the capacity to do so
Variation in root morphology amongst tree species influences soil hydraulic conductivity and macroporosity
Natural approaches to flood risk management are gaining interest as sustainable flood mitigation options. Targeted tree planting has the potential to reduce local flood risk, however attention is generally focused on the hydrological impacts of catchment afforestation linked to generic tree features, whilst the species-specific impacts of trees on soil hydrology remain poorly understood. This study compared effects of different tree species on soil hydraulic properties. Monocultures of Alnus glutinosa (common alder), Fraxinus excelsior (European ash), Fagus sylvatica (European beech), Betula pendula (silver birch), Castanea sativa (sweet chestnut), Quercus robur (English oak) and Acer pseudoplatanus (sycamore maple) were used to determine effects of tree species identity on soil hydraulic properties (near-saturated K and soil water retention) in a sandy loam soil, North Wales, United Kingdom. The interaction of F. excelsior root properties and soil class on hydraulic conductivity was also examined in four different soils (Rendzic Leptosol, Haplic Luvisol, Dystric Fluvic Cambisol and Dystric Gleysol) across England and Wales. Fine root biomass (FRB) and morphological characteristics were determined at three depths (0–0.1, 0.1–0.2 and 0.2–0.3 m) and complemented by in situ surface measurement of soil hydraulic conductivity. Root morphological traits were closely associated with species identity and pore-size distribution, and FRB was strongly correlated with soil hydraulic conductivity (R2 = 0.64 for 0–0.1 m depth FRB; R2 = 0.69 for 0.1–0.2 m depth FRB). Fine root biomass of F. excelsior was sixfold greater than C. sativa (p < 0.001), and the frequency of 0.01 mm radius soil pores under F. excelsior was twice that of Q. robur. Near-saturated hydraulic conductivity under F. excelsior was 7.91 ± 1.23 cm day−1, double the mean rate of the other species. Soil classification did not significantly influence FRB (p = 0.056) or near-saturated hydraulic conductivity (p = 0.076) in the 0.0–0.1 m depth soil, but soil water retention varied with depth. Species-specific traits of trees should be considered in landscape design to maximise the local hydrological benefits of trees
Science in neo-Victorian poetry
This article considers the work of three contemporary poets and their engagement, in verse, with Victorian science. Beginning with the outlandish ‘theories’ of Mick Imlah’s ‘The Zoologist’s Bath’ (1983), it moves on to two works of biografiction – Anthony Thwaite’s poem ‘At Marychurch’ (1980), which outlines Philip Henry Gosse’s doomed attempts to unite evolution and Christianity, and Ruth Padel’s Darwin: A Life in Poems (2009). Starting off with John Glendening’s idea that science in neo-Victorian fiction, if fully embraced, provides an opportunity for self-revelation to characters, this article explores the rather less happy resolutions of each of these poems, while in addition discussing the ways in which these poems perform the formal changes and mutability discussed within them
Gene expression profiling of CD8+ T cells predicts prognosis in patients with Crohn disease and ulcerative colitis.
Crohn disease (CD) and ulcerative colitis (UC) are increasingly common, chronic forms of inflammatory bowel disease. The behavior of these diseases varies unpredictably among patients. Identification of reliable prognostic biomarkers would enable treatment to be personalized so that patients destined to experience aggressive disease could receive appropriately potent therapies from diagnosis, while those who will experience more indolent disease are not exposed to the risks and side effects of unnecessary immunosuppression. Using transcriptional profiling of circulating T cells isolated from patients with CD and UC, we identified analogous CD8+ T cell transcriptional signatures that divided patients into 2 otherwise indistinguishable subgroups. In both UC and CD, patients in these subgroups subsequently experienced very different disease courses. A substantially higher incidence of frequently relapsing disease was experienced by those patients in the subgroup defined by elevated expression of genes involved in antigen-dependent T cell responses, including signaling initiated by both IL-7 and TCR ligation - pathways previously associated with prognosis in unrelated autoimmune diseases. No equivalent correlation was observed with CD4+ T cell gene expression. This suggests that the course of otherwise distinct autoimmune and inflammatory conditions may be influenced by common pathways and identifies what we believe to be the first biomarker that can predict prognosis in both UC and CD from diagnosis, a major step toward personalized therapy
- …