Long Term and Short Term Effects of Perturbations in a Immune Network Model

In this paper we review the trajectory of a model proposed by Stauffer and Weisbuch in 1992 to describe the evolution of the immune repertoire and present new results about its dynamical behavior. Ten years later this model, which is based on the ideas of the immune network as proposed by Jerne, has been able to describe a multi-connected network and could be used to reproduce immunization and aging experiments performed with mice. Besides its biological implications, the physical aspects of the complex dynamics of this network is very interesting {\it per se}. The immunization protocol is simulated by introducing small and large perturbations (damages), and in this work we discuss the role of both. In a very recent paper we studied the aging effects by using auto-correlation functions, and the results obtained apparently indicated that the small perturbations would be more important than the large ones, since their cumulative effects may change the attractor of the dynamics. However our new results indicate that both types of perturbations are important. It is the cooperative effects between both that lead to the complex behavior which allows to reproduce experimental results.Comment: 15 pages, 5 figure

ScannerS: Constraining the phase diagram of a complex scalar singlet at the LHC

We present the first version of a new tool to scan the parameter space of generic scalar potentials, ScannerS. The main goal of ScannerS is to help distinguish between different patterns of symmetry breaking for each scalar potential. In this work we use it to investigate the possibility of excluding regions of the phase diagram of several versions of a complex singlet extension of the Standard Model, with future LHC results. We find that if another scalar is found, one can exclude a phase with a dark matter candidate in definite regions of the parameter space, while predicting whether a third scalar to be found must be lighter or heavier. The first version of the code is publicly available and contains various generic core routines for tree level vacuum stability analysis, as well as implementations of collider bounds, dark matter constraints, electroweak precision constraints and tree level unitarity.Comment: 24 pages, 4 figures, 3 tables. Project development webpage - http://gravitation.web.ua.pt/Scanner

Vowel epenthesis in children’s oral and written productions of consonant clusters

info:eu-repo/semantics/publishedVersio

How can Kiehl's engage pharmacies skin care consumers and bring them to the brand? Appendix

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Measuring and testing for gender discrimination in physician pay: English family doctors

In 2008 the income of female GPs was 70%, and their wages (income per hour) were 89%, of those of male GPs. We estimate Oaxaca decompositions using OLS models of wages (income/hours) and 2SLS models of income. The elasticity of income with respect to hours is 0.91 for female GPs and 0.29 for male GPs, so that log wage models are misspecified. The conventional discrimination measure (the unexplained difference in mean log income) is sensitive to the counterfactual (30% using male returns vs 11% using female returns), to the use of OLS vs. 2SLS (19% vs 11%, female counterfactual), but not to dropping insignificant female interactions. The unexplained pro-male difference arises because the pro male difference in regression constants offsets the pro-female difference in the effect of hours on income. We propose a set of new direct tests for within workplace gender discrimination based on a comparison of the differences in income of female and male GPs in practices with varying proportions of female GPs and with female or male senior partners. The direct tests produce mixed results. An indirect test, comparing GPs actual income with the income they report as an acceptable reward for their job, shows that female GPs are not more likely than male GPs to report that their actual income is less than acceptable income, whereas GPs from ethnic minorities and overseas qualified GPs are significantly more likely to do so.Gender discrimination. Family doctors. General practitioners. Income. Wages.

On the vulval morphology of some species of Bursaphelenchus (Nematoda: Parasitaphelenchinae)

The vulval pattern of six species of the genus Bursaphelenchus (B. abruptus, B. conicaudatus, B. fraudulentus, B. luxuriosae, B. mucronatus and B. xylophilus) was studied using scanning electron microscopy. A terminology for the vulval region structures observed is proposed herein and illustrated by micrographs and line drawings. It was shown that, of the studied species, only B. mucronatus and B. xylophilus share an identical morphology of the vulval region, all other species differing significantly from each other and from both B. mucronatus and B. xylophilus. This study indicates the diagnostic potential for variation in vulval morphology within Bursaphelenchus and it is recommended that such features are recorded in all future descriptions

On the Aging Dynamics in an Immune Network Model

Recently we have used a cellular automata model which describes the dynamics of a multi-connected network to reproduce the refractory behavior and aging effects obtained in immunization experiments performed with mice when subjected to multiple perturbations. In this paper we investigate the similarities between the aging dynamics observed in this multi-connected network and the one observed in glassy systems, by using the usual tools applied to analyze the latter. An interesting feature we show here is that the model reproduces the biological aspects observed in the experiments during the long transient time it takes to reach the stationary state. Depending on the initial conditions, and without any perturbation, the system may reach one of a family of long-period attractors. The pertrubations may drive the system from its natural attractor to other attractors of the same family. We discuss the different roles played by the small random perturbations (noise) and by the large periodic perturbations (immunizations)