The Egyptian Cardiothoracic Surgeon (ECTS - E-Journal)
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Modelling reactive diffusion in clays with two-phase-informed pore networks
No full textDevelopment of pore network models for reactive diffusion of various species in clays is presented. Networks are constructed using experimentally measured pore-space and solid-phase characteristics. This way incomplete geometrical and topological information for a given pore system can be balanced by known solid-phase properties. Opalinus Clay (OPA) is selected to demonstrate the application and validate the proposed model. OPA is modelled as anisotropic porous medium, reflecting preferential orientation of meso-porosity along clay bedding direction. Bulk diffusivities of various species (HTO, Cl- and I-) are calculated to investigate the effects of pore structure, anion exclusion and sorption. Sorption is simulated by changing the pore space, which is more realistic compared to existing reactive transport models with assumed constant pore geometry. Anion exclusion effects are simulated by introducing diffuse double layer (DDL) in the model. Results agree well with experimentally measured diffusion coefficients for transport parallel and perpendicular to the bedding direction. The proposed model is applicable to a large class of geo-materials and suitable for linking to lattice models for deformation and damage
Text mining the history of medicine
No full textHistorical text archives constitute a rich and diverse source of information, which is becoming increasingly readily accessible, due to large-scale digitisation efforts. However, it can be difficult for researchers to explore and search such large volumes of data in an efficient manner. Text mining (TM) methods can help, through their ability to recognise various types of semantic information automatically, e.g., instances of concepts (places, medical conditions, drugs, etc.), synonyms/variant forms of concepts, and relationships holding between concepts (which drugs are used to treat which medical conditions, etc.). TM analysis allows search systems to incorporate functionality such as automatically suggesting synonyms of user-entered query terms, allowing exploration of different concepts mentioned within search results or isolating documents containing specific types of relationships between concepts. However, applying TM methods to historical text can be challenging, according to differences and evolutions in vocabulary, terminology, language structure and style, compared to more modern text. In this article, we present our efforts to overcome the various challenges faced in the semantic analysis of published historical medical text dating back to the mid 19th century. Firstly, we used evidence from diverse historical medical documents from different periods to develop new resources that provide accounts of the multiple, evolving ways in which concepts, their variants and relationships amongst them may be expressed. These resources were employed to support the development of a modular processing pipeline of TM tools for robust detection of semantic information in historical medical documents with varying characteristics. We applied the pipeline to two large scale medical document archives covering wide temporal ranges as the basis for the development of a publicly accessible semantically-oriented search system. The novel resources are available for research purposes, while the processing pipeline and its modules may be used and configured within our interoperable text mining platform
The Structure of p-Aminobenzoic Acid in Water: Studies Combining UV-Vis, NEXAFS and RIXS Spectroscopies
No full textOn Achieving Energy Efficiency and Reducing CO2 Footprint in Cloud Computing
No full textWith the increasing popularity of the cloud computing model and rapid proliferation of cloud infrastructures there are increasing concerns about energy consumption and consequent impact of cloud computing as a contributor to global CO2 emissions. To date, little is known about how to incorporate energy consumption and CO2 concerns into cloud application development and deployment decision models. In this respect, this paper describes an eco-aware approach that relies on the definition, monitoring and utilization of energy and CO2 metrics combined with the use of innovative application scheduling and runtime adaptation techniques to optimize energy consumption and CO2 footprint of cloud applications as well as the underlying infrastructure. The eco-aware approach involves measuring or quantifying the energy consumption and CO2 at different levels of cloud computing, using that information to create scheduling and adaptation techniques that contribute towards reducing the energy consumption and CO2 emissions, and finally testing and validating the developed solutions in a multi-site cloud environment with the help of challenging case study applications. The experimental and validation results show the potential of the eco-aware approach to significantly reduce the CO2 footprint and consequent environmental impact of cloud applications
Applications of Microbial Cytochrome P450 Enzymes in Biotechnology and Synthetic Biology
No full textCytochrome P450 enzymes (P450s) are a superfamily of monooxygenase enzymes with enormous potential for synthetic biology applications. Across Nature, their substrate range is vast and exceeds that of other enzymes. The range of different chemical transformations performed by P450s is also substantial, and continues to expand through interrogation of the properties of novel P450s and by protein engineering studies. The ability of P450s to introduce oxygen atoms at specific positions on complex molecules makes these enzymes particularly valuable for applications in synthetic biology. This review focuses on the enzymatic properties and reaction mechanisms of P450 enzymes, and on recent studies that highlight their broad applications in the production of oxychemicals. For selected soluble bacterial P450s (notably the high-activity P450-cytochrome P450 reductase enzyme P450 BM3), variants with a multitude of diverse substrate selectivities have been generated both rationally and by random mutagenesis/directed evolution approaches. This highlights the robustness and malleability of the P450 fold, and the capacity of these biocatalysts to oxidise a wide range of chemical scaffolds. This article reviews recent research on the application of wild-type and engineered P450s in the production of important chemicals, including pharmaceuticals and drug metabolites, steroids and antibiotics. In addition, the properties of unusual members of the P450 superfamily that do not follow the canonical P450 catalytic pathway are described
Strain Evolution during Hydride Precipitation in Zircaloy-4 Observed with Synchrotron X-Ray Diffraction
No full textThe relationship between psychological distress and multiple tender points across the adult lifespan
No full textMultiple tender points are common in the population and, in studies of mid-life adults, are strongly associated with high levels of psychological distress. Whether this relationship occurs in older adults is unclear.This cross-sectional study investigated whether high levels of psychological distress would be associated with a high tender point count and whether the relationship would be moderated by age. Three thousand three hundred and seventy-nine individuals were mailed a questionnaire which included the Hospital Anxiety and Depression (HAD) scale, the Pain Catastrophising Scale (PCS), the Brief Illness Perception Questionnaire (Brief IPQ), and the Pittsburgh Sleep Quality Index (PSQI). A random sample of approximately 10% of subjects who returned the questionnaire undertook a physical assessment, including a manual tender point count assessment.A total of 2385 (71%) subjects completed the questionnaire, of whom 798 (33%) were invited to take part in the physical assessment and 290 (12%) participated. Of the 290 participants the median age was 64 years (range 34–97) and 63% were female. The median HAD score was 9 (IQR 5–14) and the median number of tender points was 3 (range 0–7).Increasing HAD score was positively and significantly associated with tender point count, but this relationship was not moderated by age. In a final multivariable model, sex, HAD score and PSQI score were independent predictors of multiple tender points.Psychological distress was associated with multiple tender points independent of age. Psychological distress and trouble sleeping were important, potentially modifiable factors associated with the outcome