Systematic Study of Fermion Masses and Mixing Angles in Horizontal SU(2) Gauge Theory

Despite its great success in explaining the basic interactions of nature, the standard model suffers from an inability to explain the observed masses of the fundamental particles and the weak mixing angles between them. We shall survey a set of possible extensions to the standard model, employing an SU(2) ``horizontal'' gauge symmetry between the particle generations, to see what light they can shed on this problem.Comment: 43 pages, 4 figures (available by postal mail on request), OZ-92/0

Detection of Leishmania infantum by PCR, serology and cellular immune response in a cohort study of Brazilian dogs

The sensitivity and specificity of PCR, serology (ELISA) and lymphoproliferative response to Leishmania antigen for the detection of Leishmania infantum infection were evaluated in a cohort of 126 dogs exposed to natural infection in Brazil. For PCR, Leishmania DNA from bone-marrow was amplified with both minicircle and ribosomal primers. The infection status and time of infection of each dog were estimated from longitudinal data. The sensitivity of PCR in parasite-positive samples was 98%. However, the overall sensitivity of PCR in post-infection samples, from dogs with confirmed infection, was only 68%. The sensitivity of PCR varied during the course of infection, being highest (78–88%) 0–135 days post-infection and declining to around 50% after 300 days. The sensitivity of PCR also varied between dogs, and was highest in sick dogs. The sensitivity of serology was similar in parasite-positive (84%), PCR-positive (86%) and post-infection (88%) samples. The sensitivity of serology varied during the course of infection, being lowest at the time of infection and high (93–100%) thereafter. Problems in determining the specificity of serology are discussed. The sensitivity and specificity of cellular responsiveness were low. These data suggest that PCR is most useful in detecting active or symptomatic infection, and that serology can be a more sensitive technique for the detection of all infected dogs

Hypercholesterolaemia and Atherosclerosis Induced in Vervet l\'lonkeys by Cholesterol-free, Semisynthetic Diets

Vervet monkeys (Cercopithecus aethiops pygerethrus) were fed diets containing 40% carbohydrate, 25% casein and 14% hydrogenated coconut oil for 6 months. Three carbohydrates were fed: glucose, fructose and sucrose. All three diets were cholesterolaemic, the most severe cholesterolaemias being observed in the fructose and sucrose groups. All diets led to aortic sudanophilia. The fructose diet resulted in the most severe atherosclerosis and sudanophilia. This study' demonstrates the feasibility of using semisynthetic, cholesterol-free diets for the induction of hyperlipaemia and atherosclerosis in monkeys

Comparing Existing Pipeline Networks with the Potential Scale of Future U.S. CO2 Pipeline Networks

AbstractInterest is growing regarding the potential size of a future U.S.-dedicated carbon dioxide (CO2) pipeline infrastructure if carbon dioxide capture and storage (CCS) technologies are commercially deployed on a large scale within the United States. This paper assesses the potential scale of the CO2 pipeline system needed under two hypothetical climate policies (WRE450 and WRE550 stabilization scenarios); a comparison is then made to the extant U.S. pipeline infrastructures used to deliver CO2 for enhanced oil recovery and to move natural gas and liquid hydrocarbons from areas of production and importation to markets. The analysis reveals that between 11,000 and 23,000 additional miles of dedicated CO2 pipeline might be needed in the United States before 2050 across these two cases. While either case represents a significant increase over the 3900 miles that comprise the existing national CO2 pipeline infrastructure, it is important to realize that the demand for additional CO2 pipeline capacity will unfold relatively slowly and in a geographically dispersed manner as new dedicated CCS-enabled power plants and industrial facilities are brought online. During the period 2010Â2030, this analysis indicates growth in the CO2 pipeline system on the order of a few hundred to less than 1000 miles per year. By comparison, during the period 1950Â2000, the U.S. natural gas pipeline distribution system grew at rates that far exceed these growth projections for a future CO2 pipeline network in the U.S. This analysis indicates that the need to increase the size of the existing dedicated CO2 pipeline system should not be seen as a major obstacle for the commercial deployment of CCS technologies in the United States. While there could be issues associated with siting specific segments of a larger national CO2 pipeline infrastructure, the sheer scale of the required infrastructure should not be seen as representing a significant impediment to U.S. deployment of CCS technologies. Document type: Repor

Methylmercury exposure and developmental neurotoxicity.

Comment on: Global methylmercury exposure from seafood consumption and risk of developmental neurotoxicity: a systematic review. [Bull World Health Organ. 2014]]]> Humans; Methylmercury Compounds; Neurotoxicity Syndromes eng https://serval.unil.ch/resource/serval:BIB_B254C52AD78C.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_B254C52AD78C2 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_B254C52AD78C2 info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_B254CA78ED67 2022-05-07T01:25:17Z openaire documents urnserval <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_B254CA78ED67 Application of a computationally efficient method to approximate gap model results with a probabilistic approach info:doi:10.5194/gmd-7-1543-2014 info:eu-repo/semantics/altIdentifier/doi/10.5194/gmd-7-1543-2014 Scherstjanoi, M. Kaplan, J. O. Lischke, H. info:eu-repo/semantics/article article 2014 Geoscientific Model Development, vol. 7, no. 4, pp. 1543-1571 urn:issn:1991-959x eng https://serval.unil.ch/resource/serval:BIB_B254CA78ED67.P001/REF.pdf http://nbn-resolving.org/urn/resolver.pl?urn=urn:nbn:ch:serval-BIB_B254CA78ED677 info:eu-repo/semantics/altIdentifier/urn/urn:nbn:ch:serval-BIB_B254CA78ED677 info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/openAccess Copying allowed only for non-profit organizations https://serval.unil.ch/disclaimer application/pdf oai:serval.unil.ch:BIB_B254D0E85D5E 2022-05-07T01:25:17Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_B254D0E85D5E Meningite purulente aigue a Listeria seeligeri chez un adulte immunocompetent. [Acute purulent Listeria seelingeri meningitis in an immunocompetent adult] info:eu-repo/semantics/altIdentifier/pmid/3082004 Rocourt, J. Hof, H. Schrettenbrunner, A. Malinverni, R. Bille, J. info:eu-repo/semantics/article article 1986-02 Schweizerische Medizinische Wochenschrift, vol. 116, no. 8, pp. 248-51 info:eu-repo/semantics/altIdentifier/pissn/0036-7672 <![CDATA[Within the genus Listeria, the species L. monocytogenes most frequently causes disease in animals and humans. L. Seeligeri, a species recently described, has been considered experimentally nonpathogenic so far. The authors report the first case of human infection in a previously healthy adult presenting with acute purulent meningitis due to L. seeligeri. The patient recovered promptly after a course of ampicillin and gentamicin, but developed severe neurological sequelae (epilepsy, hydrocephalus) one year after the acute episode. The pathogenic properties of this isolate were investigated in two experimental animal models and the results were as follows. The clinical isolate of L. seeligeri was able to colonize the spleens of adult mice without bacterial multiplication, in contrast to the type strain of L. seeligeri (no colonization) and to a L. monocytogenes strain (colonization and multiplication). Previous infection of adult mice with the clinical L. seeligeri isolate protected moderately against spleen colonization and bacterial multiplication after challenge with L. monocytogenes. No lethal effect was observed after inoculation of suckling mice with the clinical L. seeligeri isolate, in contrast to L. monocytogenes strains. Thus, L. seeligeri, previously described as experimentally nonpathogenic for mice, may in fact be a heterogeneous species regarding its pathogenicity, and include strains that may cause life-threatening diseases in humans

Non-stationary Rayleigh-Taylor instability in supernovae ejecta

The Rayleigh-Taylor instability plays an important role in the dynamics of several astronomical objects, in particular, in supernovae (SN) evolution. In this paper we develop an analytical approach to study the stability analysis of spherical expansion of the SN ejecta by using a special transformation in the co-moving coordinate frame. We first study a non-stationary spherical expansion of a gas shell under the pressure of a central source. Then we analyze its stability with respect to a no radial, non spherically symmetric perturbation of the of the shell. We consider the case where the polytropic constant of the SN shell is $\gamma=5/3$ and we examine the evolution of a arbitrary shell perturbation. The dispersion relation is derived. The growth rate of the perturbation is found and its temporal and spatial evolution is discussed. The stability domain depends on the ejecta shell thickness, its acceleration, and the perturbation wavelength.Comment: 16 page

An Atom Laser Based on Raman Transitions

In this paper we present an atom laser scheme using a Raman transition for the output coupling of atoms. A beam of thermal atoms (bosons) in a metastable atomic state $|1 >$ are pumped into a multimode atomic cavity. This cavity is coupled through spontaneous emission to a single mode of another cavity for the ground atomic state, $|2 >$. Above a certain threshold pumping rate a large number of atoms, $N_2$, builds up in this single quantum state and transitions to the ground state of the cavity become enhanced by a factor $(N_2 + 1)$. Atoms in this state are then coupled to the outside of the cavity with a Raman transition. This changes the internal state of the atom and imparts a momentum kick, allowing the atoms to leave the system.Comment: 8 pages, 4 postscript figures, uses RevTex, home page at http://online.anu.edu.au/Physics/Welcome.html (Some aspects of the exact physical model have changed from original version. Other general improvements included

Atomic Dark Matter

We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Protohalo formation can be suppressed below $M_{proto} \sim 10^3 - 10^6 M_{\odot}$ for weak scale dark matter due to Ion-Radiation interactions in the dark sector. Moreover, weak-scale dark atoms can accommodate hyperfine splittings of order 100 \kev, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds.Comment: 17 pages, 3 figure