On the classification of OADP varieties

The main purpose of this paper is to show that OADP varieties stand at an important crossroad of various main streets in different disciplines like projective geometry, birational geometry and algebra. This is a good reason for studying and classifying them. Main specific results are: (a) the classification of all OADP surfaces (regardless to their smoothness); (b) the classification of a relevant class of normal OADP varieties of any dimension, which includes interesting examples like lagrangian grassmannians. Following [PR], the equivalence of the classification in (b) with the one of quadro-quadric Cremona transformations and of complex, unitary, cubic Jordan algebras are explained.Comment: 13 pages. Dedicated to Fabrizio Catanese on the occasion of his 60th birthday. To appear in a special issue of Science in China Series A: Mathematic

Increasing prevalence of a fluoroquinolone resistance mutation amongst Campylobacter jejuni isolates from four human infectious intestinal disease studies in the United Kingdom

Background: Campylobacter jejuni is the most common bacterial cause of human infectious intestinal disease. Methods: We genome sequenced 601 human C. jejuni isolates, obtained from two large prospective studies of infectious intestinal disease (IID1 [isolates from 1993–1996; n = 293] and IID2 [isolates from 2008–2009; n = 93]), the INTEGRATE project [isolates from 2016–2017; n = 52] and the ENIGMA project [isolates from 2017; n = 163]. Results: There was a significant increase in the prevalence of the T86I mutation conferring resistance to fluoroquinolone between each of the three later studies (IID2, INTEGRATE and ENIGMA) and IID1. Although the distribution of major multilocus sequence types (STs) was similar between the studies, there were changes in both the abundance of minority STs associated with the T86I mutation, and the abundance of clones within single STs associated with the T86I mutation. Discussion: Four population-based studies of community diarrhoea over a 25 year period revealed an increase over time in the prevalence of the T86I amongst isolates of C. jejuni associated with human gastrointestinal disease in the UK. Although associated with many STs, much of the increase is due to the expansion of clones associated with the resistance mutation

Experimental assessment of unvalidated assumptions in classical plasticity theory.

This report investigates the validity of several key assumptions in classical plasticity theory regarding material response to changes in the loading direction. Three metals, two rock types, and one ceramic were subjected to non-standard loading directions, and the resulting strain response increments were displayed in Gudehus diagrams to illustrate the approximation error of classical plasticity theories. A rigorous mathematical framework for fitting classical theories to the data, thus quantifying the error, is provided. Further data analysis techniques are presented that allow testing for the effect of changes in loading direction without having to use a new sample and for inferring the yield normal and flow directions without having to measure the yield surface. Though the data are inconclusive, there is indication that classical, incrementally linear, plasticity theory may be inadequate over a certain range of loading directions. This range of loading directions also coincides with loading directions that are known to produce a physically inadmissible instability for any nonassociative plasticity model

Facilitating Pupil Thinking About Information Literacy

Whilst information literacy is frequently taught through the imposition on learners of an established framework, this paper suggests a different approach by taking a lead from James Herring’s ideas. Specifically, it provides guidance to school-based information professionals who would like to encourage their pupils to devise their own flexible, information literacy models which are unique to them. Drawing on existing material in information science and wider thought, it proposes areas for coverage and considers how information professionals may support the dynamic process of model construction. It is recommended that those who are intent on facilitating the creation of personal information literacy models help pupils to identify the roles they take on in their lives, to reflect on the information needs that result, to ascertain the information they require in particular situations, to explore their information-seeking activities, to consider means by which information can be captured and to give thought as to how the information they have accessed may be used. This framework is, however, by no means rigid and readers are, of course, free to make their own adjustments

Climate Change, Foodborne Pathogens, and Illness in Higher Income Countries

Purpose of review: We present a review of the likely consequences of climate change for foodborne pathogens and associated human illness in higher income countries. Recent findings: The relationships between climate and food are complex and hence the impacts of climate change uncertain. This makes it difficult to know which foodborne pathogens will be most affected, what the specific effects will be, and on what timescales changes might occur. Hence, a focus upon current capacity and adaptation potential against foodborne pathogens is essential. We highlight a number of developments that may enhance preparedness for climate change. These include: • Adoption of novel surveillance methods, such as syndromic methods, to speed up detection and increase the fidelity of intervention in foodborne outbreaks • Genotype based approaches to surveillance of food pathogens to enhance spatio-temporal resolution in tracing and tracking of illness • Ever increasing integration of plant, animal and human surveillance systems, one-health, to maximize potential for identifying threats • Increased commitment to cross-border (global) information initiatives (including big data) • Improved clarity regarding the governance of complex societal issues such as the conflict between food safety and food waste • Strong user centric (social) communications strategies to engage diverse stakeholder groups Summary: The impact of climate change upon foodborne pathogens and associated illness is uncertain. This emphasises the need to enhance current capacity and adaptation potential against foodborne illness. A range of developments are explored in this paper to enhance preparedness

O conceito de “Dispositivo universal” (Universalapparat) em Günther Anders

Encontra-se em curso, sensivelmente no último meio século, a finalização de um processo de planetarização da Tecnologia, que, na ordem das causas, terá sido mais proximamente determinado pela Globalização político-económica urdida e imposta pelo Neoliberalismo e mais remotamente influenciado por sucessivas revoluções industriais, desde o século XVIII. Ele implicou uma transformação na própria natureza da Tecnologia, fazendo com que deixasse de ser mero meio (utensílio, ferramenta, instrumento) para determinados fins e se tivesse tornado num ambiente vital e existencial. Günther Anders foi um atento e perspicaz observador e crítico desse fenómeno, que, no seu jargão, concebeu como o do advento de um “Dispositivo universal” (Universalapparat). Dedica-se a primeira parte deste artigo à releitura da interpretação que esse filósofo alemão fez da sua suposta génese e evolução. Na segunda parte, analisa-se esse conceito. Explora-se, na terceira parte, duas consequências filosóficas maiores desse fenómeno.More or less in the last half century, a process of planetarization of Technology is underway, which in the order of causes will have been more directly determined by the politicaleconomic Globalization woven and imposed by the so-called Neoliberalism and more remotely influenced by successive industrial revolutions since the 18th century. It implied a transformation in the nature of Technology, ceasing to be a mere means (utensil, tool, instrument) for certain purposes and becoming a vital and existential environment. Günther Anders was an attentive, perceptive and critical observer of this phenomenon that, in his jargon, he conceived as the advent of a “Universal apparatus” (Universalapparat). I dedicate the first part of this article to reread the German philosopher’s interpretation of his supposed genesis and evolution. In the second part, I analyze this concept. In the third part, I explore two main philosophical consequences of this phenomenon

CmeABC multidrug efflux pump contributes to antibiotic resistance and promotes 'Campylobacter jejuni' survival and multiplication in 'Acanthamoeba polyphaga'

Campylobacter jejuni is a foodborne pathogen recognized as the leading cause of human bacterial gastroenteritis. The wide use of antibiotics in medicine and in animal husbandry has led to an increased incidence of antibiotic resistance in Campylobacter In addition to a role in multidrug resistance, the Campylobacter CmeABC RND-type efflux pump, which is associated with multidrug resistance (MDR), may also be involved in virulence. As a vehicle of pathogenic microorganisms, the protozoan Acanthamoeba is a good model for the investigation of bacterial survival in the environment and molecular mechanisms of pathogenicity. The interaction between C. jejuni 81-176 and A. polyphaga was investigated in this study by using a modified gentamicin protection assay. In addition, a possible role for the CmeABC MDR pump in this interaction was explored. Here we report that this MDR pump is beneficial for the intracellular survival and multiplication of C. jejuni in A. polyphaga, but is dispensable for biofilm formation and motility.Importance The endosymbiotic relationship between amoebae and microbial pathogens may contribute to persistence and spreading of the latter in the environment, which has significant implications to human health. In this study we found that Campylobacter jejuni was able to survive and multiply inside Acanthamoeba. polyphaga Since these microorganisms can co-exist in the same environment (e.g. in poultry farms), the latter may increase the risk of infection with Campylobacter Our data suggests that, in addition to its role in antibiotic resistance, the CmeABC MDR efflux pump also plays a role in bacterial survival within amoebae. Furthermore, we demonstrated a synergistic effect of the CmeABC MDR efflux pump and TetO on bacterial resistance to tetracycline. Due to its role both in antibiotic resistance and virulence of C. jejuni, the CmeABC MDR efflux pump could be considered as a good target for the development of antibacterial drugs against this pathogen

Comparative genomics of Escherichia coli isolated from patients with inflammatory bowel disease

<p>Abstract</p> <p>Background</p> <p>Inflammatory bowel disease (IBD) is used to describe a state of idiopathic, chronic inflammation of the gastrointestinal tract. The two main phenotypes of IBD are Crohn's disease (CD) and ulcerative colitis (UC). The major cause of IBD-associated mortality is colorectal cancer. Although both host-genetic and exogenous factors have been found to be involved, the aetiology of IBD is still not well understood. In this study we characterized thirteen <it>Escherichia coli </it>strains from patients with IBD by comparative genomic hybridization employing a microarray based on 31 sequenced <it>E. coli </it>genomes from a wide range of commensal and pathogenic isolates.</p> <p>Results</p> <p>The IBD isolates, obtained from patients with UC and CD, displayed remarkably heterogeneous genomic profiles with little or no evidence of group-specific determinants. No IBD-specific genes were evident when compared with the prototypic CD isolate, LF82, suggesting that the IBD-inducing effect of the strains is multifactorial. Several of the IBD isolates carried a number of extraintestinal pathogenic <it>E. coli </it>(ExPEC)-related virulence determinants such as the <it>pap</it>, <it>sfa</it>, <it>cdt </it>and <it>hly </it>genes. The isolates were also found to carry genes of ExPEC-associated genomic islands.</p> <p>Conclusions</p> <p>Combined, these data suggest that <it>E. coli </it>isolates obtained from UC and CD patients represents a heterogeneous population of strains, with genomic profiles that are indistinguishable to those of ExPEC isolates. Our findings indicate that IBD-induction from <it>E. coli </it>strains is multifactorial and that a range of gene products may be involved in triggering the disease.</p