183 research outputs found

    Bounds on the renormalized couplings in an SU(2)_L \otimes SU(2)_R symmetric Yukawa model

    Full text link
    The vacuum stability lower bound on the mass of the Higgs boson is numerically investigated in an SU(2)LSU(2)RSU(2)_L \otimes SU(2)_R symmetric Yukawa model, which describes two heavy degenerate fermion doublets in the limit of vanishing gauge couplings. Good agreement with perturbation theory is found, although the couplings are strong. The upper bound on the fermion mass and renormalized Yukawa coupling is also determined in the part of bare parameter space where reflection positivity has been proven.Comment: 9 pages + 2 figures (appended as postscript files

    A homeostatic function of CXCR2 signalling in articular cartilage

    Get PDF
    Funding This work was funded by Arthritis Research UK (grants 17859, 17971, 19654), INNOCHEM EU FP6 (grant LSHB-CT-2005-51867), MRC (MR/K013076/1) and the William Harvey Research FoundationPeer reviewedPublisher PD

    Swimming by reciprocal motion at low Reynolds number

    Get PDF
    Biological microorganisms swim with flagella and cilia that execute nonreciprocal motions for low Reynolds number (Re) propulsion in viscous fluids. This symmetry requirement is a consequence of Purcell's scallop theorem, which complicates the actuation scheme needed by microswimmers. However, most biomedically important fluids are non-Newtonian where the scallop theorem no longer holds. It should therefore be possible to realize a microswimmer that moves with reciprocal periodic body-shape changes in non-Newtonian fluids. Here we report a symmetric 'micro-scallop', a single-hinge microswimmer that can propel in shear thickening and shear thinning (non-Newtonian) fluids by reciprocal motion at low Re. Excellent agreement between our measurements and both numerical and analytical theoretical predictions indicates that the net propulsion is caused by modulation of the fluid viscosity upon varying the shear rate. This reciprocal swimming mechanism opens new possibilities in designing biomedical microdevices that can propel by a simple actuation scheme in non-Newtonian biological fluids

    A novel haemocytometric COVID-19 prognostic score developed and validated in an observational multicentre European hospital-based study

    Get PDF
    COVID-19 induces haemocytometric changes. Complete blood count changes, including new cell activation parameters, from 982 confirmed COVID-19 adult patients from 11 European hospitals were retrospectively analysed for distinctive patterns based on age, gender, clinical severity, symptom duration, and hospital days. The observed haemocytometric patterns formed the basis to develop a multi-haemocytometric-parameter prognostic score to predict, during the first three days after presentation, which patients will recover without ventilation or deteriorate within a two-week timeframe, needing intensive care or with fatal outcome. The prognostic score, with ROC curve AUC at baseline of 0.753 (95% CI 0.723-0.781) increasing to 0.875 (95% CI 0.806-0.926) on day 3, was superior to any individual parameter at distinguishing between clinical severity. Findings were confirmed in a validation cohort. Aim is that the score and haemocytometry results are simultaneously provided by analyser software, enabling wide applicability of the score as haemocytometry is commonly requested in COVID-19 patients

    Association between overweight, obesity and self-perceived job insecurity in German employees

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Recent studies have shown an association between job insecurity and morbidity as well as mortality, however until now, knowledge about a potential association between job insecurity and overweight or obesity has been lacking.</p> <p>Methods</p> <p>In order to identify a possible association between job insecurity and overweight or obesity, we analysed data from the German Socioeconomic Panel (GSOEP) 2004/2005, a longitudinal study of private households in Germany. In this representative cohort of the German adult population, living and working conditions were observed. Data on Body Mass Index (BMI) and self-perceived probability of job loss within the next 2 years were available for 10,747 adults either employed or attending training programs.</p> <p>Results</p> <p>We identified 5,216 (49%) individuals as being overweight (BMI > 25 kg/m<sup>2</sup>) and 1,358(13%) individuals as being obese (BMI > 30 kg/m<sup>2</sup>). A total of 5,941 (55%) participants reported having concerns regarding job insecurity. In the multivariate analysis - after adjustment for relevant confounders - a statistically significant association between obesity and job insecurity (100% probability for losing the job in the following two years) could be observed with an adjusted odds ratio of 2.55 (95% confidence interval: 1.09-5.96).</p> <p>Conclusions</p> <p>Because of these results, we were able to conclude that overweight and obese persons perceive job insecurity more often than their normal weight counterparts in Germany and that the concurrence of obesity and job insecurity might lead employees into a vicious cycle. Further research with an emphasis on the occupational setting might be necessary in order to establish useful preventive programmes at the workplace.</p

    The Role of Transporters in the Pharmacokinetics of Orally Administered Drugs

    Get PDF
    Drug transporters are recognized as key players in the processes of drug absorption, distribution, metabolism, and elimination. The localization of uptake and efflux transporters in organs responsible for drug biotransformation and excretion gives transporter proteins a unique gatekeeper function in controlling drug access to metabolizing enzymes and excretory pathways. This review seeks to discuss the influence intestinal and hepatic drug transporters have on pharmacokinetic parameters, including bioavailability, exposure, clearance, volume of distribution, and half-life, for orally dosed drugs. This review also describes in detail the Biopharmaceutics Drug Disposition Classification System (BDDCS) and explains how many of the effects drug transporters exert on oral drug pharmacokinetic parameters can be predicted by this classification scheme

    Superposed renewal processes: a Markov renewal approach

    No full text
    Lam and Lehoczky (1991) have recently given a number of extensions of classical renewal theorems to superpositions of p independent renewal processes. In this article we want to advertise an approach that more explicitly uses a Markov renewal theoretic framework and thus leads to a simplified derivation of their main results together with a number of new ones. Those include a Stone-type decomposition for the resulting Markov renewal measure and a number of convergence rate results which extend the corresponding results for single renewal processes. (orig.)Available from TIB Hannover: RO 7057(1995,9) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

    A survey of database design transformations based on the entity-relationship model

    No full text
    At present, the Entity-Relationship (ER) model is the most important paradigm for conceptual database design. Since the model was introduced in the mid-seventies, a large body of literature has been published on transforming conceptual ER schemas or diagrams into logical data models. The purpose of this paper is to survey this literature. A major focus is on transformation approaches from the ER model to traditional data models, i.e., to the relational, the network, or the hierarchical model; in addition, the process of reverse engineering is considered, i.e., transformations from a logical model back into the ER model and an overview of direct transformations between logical models is presented. (orig.)Available from TIB Hannover: RO 7057(1994,14) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDeutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman

    Transforming relational database schemas into object-oriented schemas according to ODMG-93

    No full text
    Many database applications are currently confronted with the problem of migrating from relational to object-oriented systems. A central task in such a process is schema conversion, which so far has to be done in a way that specifically depends on the target system. Recently, the ODMG-93 proposal has established a framework in which the core aspects of an object-oriented schema can be made precise, so that it becomes possible to do schema conversions in a system-independent way, by using the ODMG model as target. This paper presents a methodology for transforming relational schemas into object-oriented ones according to ODMG-93, thereby rendering it possible to do reverse engineering computer-assisted, and to automize database migrations. Essentially, the methodology is a three-step process who first goal is to complete a given relational schema, i.e., to make the semantic information it carries as explicit as possible using a variety of data dependencies. A completed schema is then tranformed into an ODMG schema in a straightforward way, basically by generating classes from relation schemas. However, the result will in general not yet be optimal from an object-oriented perspective; so the initial object-oriented schema is finally improved to better exploit the options available in the object-oriented paradigm. (orig.)SIGLEAvailable from TIB Hannover: RO 7057(1995,11) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDeutsche Forschungsgemeinschaft (DFG), Bonn (Germany)DEGerman
    corecore