Bounds on the electromagnetic interactions of excited spin-3/2 leptons

We discuss possible deviations from QED produced by a virtual excited spin-3/2 lepton in the reaction $e^+e^- \longrightarrow 2\gamma$. Data recorded by the OPAL Collaboration at a c.m. energy $\sqrt{s} = 183 GeV$ are used to establish bounds on the nonstandard-lepton mass and coupling strengths.Comment: Latex, 5 pages, 7 ps figures. To be published in Phys. Rev.

Non-parametric comparison of histogrammed two-dimensional data distributions using the Energy Test

When monitoring complex experiments, comparison is often made between regularly acquired histograms of data and reference histograms which represent the ideal state of the equipment. With the larger HEP experiments now ramping up, there is a need for automation of this task since the volume of comparisons could overwhelm human operators. However, the two-dimensional histogram comparison tools available in ROOT have been noted in the past to exhibit shortcomings. We discuss a newer comparison test for two-dimensional histograms, based on the Energy Test of Aslan and Zech, which provides more conclusive discrimination between histograms of data coming from different distributions than methods provided in a recent ROOT release.The Science and Technology Facilities Council, U

Phenomenological study of the electronic transport coefficients of graphene

Using a semi-classical approach and input from experiments on the conductivity of graphene, we determine the electronic density dependence of the electronic transport coefficients -- conductivity, thermal conductivity and thermopower -- of doped graphene. Also the electronic density dependence of the optical conductivity is obtained. Finally we show that the classical Hall effect (low field) in graphene has the same form as for the independent electron case, characterized by a parabolic dispersion, as long as the relaxation time is proportional to the momentum.Comment: 4 pages, 1 figur

Exact Solution of Ising Model on a Small-World Network

We present an exact solution of a one-dimensional Ising chain with both nearest neighbor and random long-range interactions. Not surprisingly, the solution confirms the mean field character of the transition. This solution also predicts the finite-size scaling that we observe in numerical simulations.Comment: 9 pages, 7 figures, submitted to pr

GeMs/GSAOI observations of La Serena 94: an old and far open cluster inside the solar circle

Physical properties were derived for the candidate open cluster La Serena 94, recently unveiled by the VVV collaboration. Thanks to the exquisite angular resolution provided by GeMS/GSAOI, we could characterize this system in detail, for the first time, with deep photometry in JHK$_{s}$ - bands. Decontaminated JHK$_{s}$ diagrams reach about 5 mag below the cluster turnoff in H. The locus of red clump giants in the colour - colour diagram, together with an extinction law, was used to obtain an average extinction of $A_V =14.18 \pm 0.71$. The same stars were considered as standard - candles to derive the cluster distance, $8.5 \pm 1.0$ kpc. Isochrones were matched to the cluster colour - magnitude diagrams to determine its age, $\log{t(yr)}=9.12\pm 0.06$, and metallicity, $Z=0.02\pm0.01$. A core radius of $r_{c}=0.51\pm 0.04$ pc was found by fitting King models to the radial density profile. By adding up the visible stellar mass to an extrapolated mass function, the cluster mass was estimated as $M=(2.65\pm0.57) \times 10^3$ M$_{\odot}$, consistent with an integrated magnitude of $M_{K}=-5.82\pm0.16$ and a tidal radius of $r_{t}=17.2\pm2.1$ pc. The overall characteristics of La Serena 94 confirm that it is an old open cluster located in the Crux spiral arm towards the fourth Galactic quadrant and distant $7.30\pm 0.49$ kpc from the Galactic centre. The cluster distorted structure, mass segregation and age indicate that it is a dynamically evolved stellar system.Comment: 16 pages, 24 figures, 2 Tables, accepted by MNRAS; corrected typo

Prevalence of anti-Leptospira spp. antibodies in cows in the municipalities of Nova Guarita and Nova Santa Helena, Mato Grosso State, Brazil.

EN-US: Frequently, leptospirosis is related to reproductive problems in livestock, such as abortion, increased embryonic mortality and stillbirths. Unfortunately, there are few reports addressing the prevalence of the disease in cattle in the North of Mato Grosso State (MT), Brazil. The aim of the present study was to determine the presence of anti-Leptospira spp. antibodies in cattle in the municipalities of Nova Guarita and Nova Santa Helena, MT. Nine hundred and eighty blood samples were taken from cows aged ≥24 months from 49 farms slaughtered in Sinop, MT. Microscopic Agglutination Test was used for the detection of anti-Leptospira spp. antibodies. The animal prevalence was 17.9% (95% CI = 15.6-20.5%). The prevalence observed in the municipalities Nova Guarita and Nova Santa Helena was 13.4% (95% CI = 12.8-14.1%) and 23.2% (95% CI = 22.0-24.3%), respectively. The herd prevalence was 83.6% (95% CI = 79.4-87.8%). The most frequent serovar was Wolffi (47.7%), followed by Hardjo (16.1%), Hardjo - Bolivia sample (11.0%), Australis (7.4%), Grippotyphosa (4.6%), Pomona (3.4%), Batavie (3.4%), Autumnalis (1.7%), Icterohaemorrhagiae (1.7%), Hebdomadis (1.1%), Hardjo-bovis (1.1%), and Castellonis (0.5%). Infection by Leptospira spp. is endemic in both municipalities, reinforcing the need for new epidemiological studies to subsidize the control of the disease in Mato Grosso. | PT-BR: A leptospirose está frequentemente relacionada a problemas reprodutivos em rebanhos bovinos, como abortamentos, aumento da mortalidade embrionária e nascimento de bezerros fracos. Infelizmente, existem poucos estudos envolvendo a prevalência da enfermidade em bovinos na região norte do Estado de Mato Grosso, Brasil. O presente estudo teve como objetivo determinar a presença de anticorpos anti-Leptospira spp. em rebanhos bovinos dos municípios de Nova Guarita e Nova Santa Helena, Mato Grosso. No total, 980 amostras de sangue foram coletadas de fêmeas bovinas oriundas de 49 propriedades, todas com idade ≥ 24 a meses abatidas em abatedouro frigorifico localizado no município de Sinop, MT. O teste de Soroaglutinação Microscópica foi utilizado para a detecção de anticorpos anti-Leptospira spp. A prevalência animal foi de 17,9 % (95% IC = 15,6?20,5%). A prevalência observada entre os municípios de Nova Guarita e Nova Santa Helena foi de 13,4% (95% IC = 12,8?14,1%) e 23,2% (95% IC = 22,0?24,3%), respectivamente. A prevalência de propriedades foco foi de 83,6% (95% IC = 79,4?87,8%). A sorovariedade mais frequente foi a Wolffi (47,7%), seguido pelas sorovariedades Hardjo (16,1%); Hardjo amostra Bolívia (11,0%); Australis (7,4%); Grippotyphosa (4,6%); Pomona (3,4%); Batavie (3,4%); Autumnalis (1,7%); Icterohaemorrhagiae (1,7%); Hebdomadis (1,1%); Hardjobovis (1,1%) e Castellonis (0,5%). Concluiu-se que a infecção por Leptospira spp. é endêmica nos dois os municípios, reiterando a necessidade de novos estudos epidemiológicos para subsidiar o controle da doença em Mato Grosso