Substructures in lens galaxies: PG1115+080 and B1555+375, two fold configurations

We study the anomalous flux ratio which is observed in some four-image lens systems, where the source lies close to a fold caustic. In this case two of the images are close to the critical curve and their flux ratio should be equal to unity, instead in several cases the observed value differs significantly. The most plausible solution is to invoke the presence of substructures, as for instance predicted by the Cold Dark Matter scenario, located near the two images. In particular, we analyze the two fold lens systems PG1115+080 and B1555+375, for which there are not yet satisfactory models which explain the observed anomalous flux ratios. We add to a smooth lens model, which reproduces well the positions of the images but not the anomalous fluxes, one or two substructures described as singular isothermal spheres. For PG1115+080 we consider a smooth model with the influence of the group of galaxies described by a SIS and a substructure with mass $\sim 10^{5} M_{\odot}$ as well as a smooth model with an external shear and one substructure with mass $\sim 10^{8} M_{\odot}$ . For B1555+375 either a strong external shear or two substructures with mass $\sim 10^{7} M_{\odot}$ reproduce the data quite well.Comment: 26 pages, updated bibliography, Accepted for publication in Astrophysics & Space Scienc

Twee praktijkproeven betreffende de competatieve uitsluiting van Salmonella en Campylobacter jejuni bij kuikens door middel van een bepaald mengsel van bacteriestammen

Het rapport beschrijft twee veldproeven waarin de beschermende werking van intestinale flora bij slachtkuikens tegen kolonisatie met Salmonella en C.jejuni werd onderzocht. De proeven werden uitgevoerd op een mestbedrijf met twee identieke kuikenhokken. Eendagskuikens in het ene hok kregen met het drinkwater beschermende flora toegediend, terwijl de kuikens in het andere hok niet werden behandeld. De intestinale flora bleek geen effect te hebben op de kolonisatie met C.jejuni. Met betrekking tot de Salmonella-kolonisatie konden geen conclusies worden getrokken omdat in beide proeven de eendagskuikens reeds met Salmonella waren besmet. In de eerste proef verdween deze besmetting spoedig, doch in de tweede proef handhaafde de Salmonella- besmetting zich tot het einde van de mestperiode. Er kon worden aangetoond dat de toegediende flora geen nadelige effecten op gezondheid of groei van de dieren opleverde.Abstract not availableVHIRIV

HST Observations of Gravitationally Lensed QSOs

Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing galaxy responsible for the image splitting; (3) improving the astrometric accuracy on the positions of the unresolved QSO images and of the lens; (4) resolving extended lensed structures from the QSO hosts into faint NIR or optical rings or arcs. These observations have helped to break some degeneracies on the lens potential, to probe the galaxy evolution and to reconstruct the true shape of the QSO host with an increased angular resolution

In vivo characterization of Lactobacillus johnsonii FI9785 for use as a defined competitive exclusion agent against bacterial pathogens in poultry

Aims: To test the efficacy of Lactobacillus johnsonii FI9785 in reducing the colonization and shedding of Salmonella enterica serotype Enteritidis, Escherichia coli O78:K80 and Clostridium perfringens in poultry. Methods and Results: Specific pathogen-free chicks (1 day old) were dosed with a single oral inoculum of 1 x 10(9) CFU. Lactobacillus johnsonii FI9785 and 24 h later were challenged in separate experiments with S. Enteritidis (S1400, nal(r)) and E. coli O78:K80 (EC34195, nal(r)). There were no significant effects against S. Enteritidis whereas colonization of the small intestine by E. coli O78:K80 was reduced significantly. Both S. Enteritidis and E. coli colonized the caeca and colon to levels equivalent to control birds and there was no reduction in shedding as assessed by a semi-quantitative cloacal swabbing technique. Specific pathogen-free chicks (20 day old) were dosed with a single oral inoculum of 1 x 10(9) CFU L. johnsonii FI9785 and 24 h later were challenged with C. perfringens. A single oral dose of L. johnsonii FI9785 was sufficient to suppress all aspects of colonization and persistence of C. perfringens. Conclusions: Lactobacillus johnsonii FI9785 may be given to poultry for use as a competitive exclusion agent to control C. perfringens. Significance and Impact of the Study: Lactobacillus johnsonii FI9785 may be a valuable tool to control the endemic disease of necrotic enteritis, thereby reducing economic losses associated with reduced use of antimicrobials in the poultry industry

Evaluating the therapeutic effects of museum object handling with hospital patients: A review and initial trial of wellbeing measures

Arts therapy interventions within health care produce positive outcomes for patients, staff and carers, though little rigorous evaluation of these activities is conducted using clinically accepted measures. Similarly, heritage-specific therapeutic interventions offer comparable potential to increase well-being. Although museums and galleries have significant capacity to contribute to health and social care, widespread implementation is impeded by lack of robust clinical data quantifying the impact of such interventions. Measurement scales for psychological well-being, quality of life and health status were reviewed for their suitability to evaluate well-being in hospital patients before and after 30-minute museum object handling sessions. Measures were short-listed using selection criteria of internal and external validity, practicality and sensitivity. Focus on usage in health care, breadth of application, ease of administration and degree of responsiveness informed the choice of optimum measures for preliminary research with female oncology patients (n=40). Findings indicated effectiveness of selected measures (Positive Affect Negative Affect Scale; PANAS and Visual Analogue Scale; VAS) for heritage-specific interventions