Radiative Decays, Nonet Symmetry and SU(3) Breaking

We re-examine the problem of simultaneously describing in a consistent way all radiative and leptonic decays of light mesons (V -> P gamma, P -> V gamma, P -> gamma gamma, V -> e^+ e^-). For this purpose, we rely on the Hidden Local Symmetry model in both its anomalous and non--anomalous sectors. We show that the SU(3) symmetry breaking scheme proposed by Bando, Kugo and Yamawaki, supplemented with nonet symmetry breaking in the pseudoscalar sector, allows one to reach a nice agreement with all data, except for the K^{*+/-} radiative decay. An extension of this breaking pattern allows one to account for this particular decay mode too. Considered together, the whole set of radiative decays provides a pseudoscalar mixing angle theta_P ~ -11^o and a value for theta_V which is ~ 3^o from that of ideal mixing. We also show that it is impossible, in a practical sense, to disentangle the effects of nonet symmetry breaking and those of glue inside the eta', using only light meson decays.Comment: 36 pages. Published versio

Genomic analysis of two phlebotomine sand fly vectors of Leishmania from the New and Old World.

Phlebotomine sand flies are of global significance as important vectors of human disease, transmitting bacterial, viral, and protozoan pathogens, including the kinetoplastid parasites of the genus Leishmania, the causative agents of devastating diseases collectively termed leishmaniasis. More than 40 pathogenic Leishmania species are transmitted to humans by approximately 35 sand fly species in 98 countries with hundreds of millions of people at risk around the world. No approved efficacious vaccine exists for leishmaniasis and available therapeutic drugs are either toxic and/or expensive, or the parasites are becoming resistant to the more recently developed drugs. Therefore, sand fly and/or reservoir control are currently the most effective strategies to break transmission. To better understand the biology of sand flies, including the mechanisms involved in their vectorial capacity, insecticide resistance, and population structures we sequenced the genomes of two geographically widespread and important sand fly vector species: Phlebotomus papatasi, a vector of Leishmania parasites that cause cutaneous leishmaniasis, (distributed in Europe, the Middle East and North Africa) and Lutzomyia longipalpis, a vector of Leishmania parasites that cause visceral leishmaniasis (distributed across Central and South America). We categorized and curated genes involved in processes important to their roles as disease vectors, including chemosensation, blood feeding, circadian rhythm, immunity, and detoxification, as well as mobile genetic elements. We also defined gene orthology and observed micro-synteny among the genomes. Finally, we present the genetic diversity and population structure of these species in their respective geographical areas. These genomes will be a foundation on which to base future efforts to prevent vector-borne transmission of Leishmania parasites

Microbiological counting in lamb carcasses from an abattoir in São Paulo, Brazil Contagens microbiológicas em carcaças ovinas de um abatedouro de São Paulo, Brasil

The consumption of lamb meat in Brazil has increased in the last years but little information about the microbiological quality of this product is available. To evaluate the hygienic-sanitary conditions of lamb carcasses, the quantification of microorganism populations indicators (mesophiles and psychrotrophs; total and thermotolerant coliforms; Escherichia coli; moulds and yeasts) and the pathogenic microorganisms indentification (Salmonella sp. and Listeria spp.) were performed. A total of 60 lamb carcasses were sampled from one abattoir in São Paulo. Swab samples were collected from three points (forequarter, back and hindquarter) on the muscle surface after carcasses final washing. Statistical analysis consisted of descriptive evaluation of the results whose counts were grouped by intervals of microorganism populations. Counts ranged from 1.0 x 10¹ to 8.0 x 10(4) colony-forming unit cm-2 (CFU cm-2) for mesophiles; 1.0 x 10(0) to 4.4 x 10(4)CFU cm-2 for psychrotrophs; < 1.0 x 10(0) to 4.4 x 10(4)CFU cm-2 for moulds and yeasts; < 0.3 to > 32.0 most probable number/cm² (MPN cm-2) for total and thermotolerant coliforms and Escherichia coli. Salmonella sp. and Listeria spp. were not found in any of the carcasses. Most carcasses presented low counts for all microorganisms. Overall results may be explained by the small size of the industry where the study was taken. Results suggest that good microbiological quality lamb meat is possible to be obtained, but improvement in hygienic-sanitary conditions is still required.<br>O consumo de carne ovina tem aumentado nos últimos anos, no Brasil. Entretanto, pouca informação sobre a qualidade desse produto está disponível. Com o intuito de avaliar as condições higiênico-sanitárias das carcaças ovinas, foram realizadas a quantificação das populações de microrganismos indicadores (mesófilos e psicrotróficos; coliformes totais e termotolerantes; Escherichia coli; bolores e leveduras) e a identificação de microrganismos patogênicos (Salmonella sp. and Listeria spp.). Um total de 60 carcaças foram amostradas em um frigorífico, em São Paulo, entre fevereiro e dezembro de 2006. Suabes foram coletados em três pontos (dianteiro, lombo e traseiro), na superfície muscular das carcaças, após a lavagem final destas. A análise estatística consistiu na avaliação descritiva dos resultados cujas contagens foram agrupadas em intervalos populacionais. As contagens variaram de 1,0 x 10¹ a 8,0 x 10(4)UFC cm-2 para mesófilos; de 1,0 x 10(0) a 4,4 x 10(4)UFC cm-2 para psicrotróficos; de < 1,0 x 10(0) a 4,4 x 10(4)UFC cm-2 para bolores e leveduras; de < 0,3 a > 32,0 NMP cm-2 para coliformes totais e termotolerantes; e Escherichia coli. Salmonella sp. e Listeria spp. não foram detectadas em nenhuma das amostras coletadas nas carcaças. A maioria das carcaças apresentou baixas contagens para todas as categorias de microrganismos. Os resultados encontrados podem ser explicados pelo pequeno tamanho da indústria onde o trabalho foi realizado e sugerem que carne ovina de boa qualidade microbiológica pode ser obtida. No entanto, melhorias nas condições higiênico-sanitárias ainda são necessárias