Anomalous diffusion on crumpled wires in two dimensions

It is investigated the statistical properties of random walks evolving on real configurations of a crumpled wire rigidly jammed in two dimensions. These crumpled hierarchical structures with complex topology are obtained from a metallic wire injected at a constant rate into a transparent planar cell of 20cm of diameter. The observed diffusion is anomalous with an exponent very close to that obtained at the threshold of two dimensional percolation. A comparison of the system studied in this paper with other systems of physical interest is also made, and an experimental consequence of our results is discussed.Comment: 10 pages including 4 figures. Physica A (2006). Preprin

CDM Accelerating Cosmology as an Alternative to LCDM model

A new accelerating cosmology driven only by baryons plus cold dark matter (CDM) is proposed in the framework of general relativity. In this model the present accelerating stage of the Universe is powered by the negative pressure describing the gravitationally-induced particle production of cold dark matter particles. This kind of scenario has only one free parameter and the differential equation governing the evolution of the scale factor is exactly the same of the $\Lambda$CDM model. For a spatially flat Universe, as predicted by inflation ($\Omega_{dm}+\Omega_{baryon}=1$), it is found that the effectively observed matter density parameter is $\Omega_{meff} = 1- \alpha$, where $\alpha$ is the constant parameter specifying the CDM particle creation rate. The supernovae test based on the Union data (2008) requires $\alpha\sim 0.71$ so that $\Omega_{meff} \sim 0.29$ as independently derived from weak gravitational lensing, the large scale structure and other complementary observations.Comment: 6 pages, 3 figure

First report of anthracnose caused by Colletotrichum spaethianum on Allium fistulosum in Brazil

The Welch onion (Allium fistulosum L.) is widely grown in temperate and subtropical regions worldwide and has many important culinary uses. The occurrence of anthracnose on Welch onion has been reported in Korea and is caused by Colletotrichum circinans (Kim et al. 2008). Since 2012, symptoms typical of anthracnose have been observed on Welch onions in a vegetable garden located in the Japanese Colony of Manaus, Amazonas, Brazil (59°59′06″ W; 03°04′16″ S). This disease occurred in 50% of the seedlings and the symptoms consist of brown necrotic spots that extend along the entire leaf. Acervuli collected directly from the leaves were plated onto potato dextrose agar (PDA) and then incubated at 25°C for three to four days. Single-spore cultures were obtained from three isolates from different plants. On PDA medium, the isolates initially produced white colonies, which then turned gray and had an orange-colored conidial mass. On Spezieller Nährstoffarmer Agar (SNA) medium (Leslie and Summerell, 2006), they formed numerous black structures such as sclerotia, setae, and acervuli. Conidia on SNA are hyaline, aseptate, curved or slightly curved, with a rounded apex and truncated base that is 13.1 to 20.2 μm long and 3.3 to 4.0 μm wide. The appressoria are solitary or in loose groups, dark brown, irregularly shaped, sometimes partially lobed, smooth-walled, and from 5.6 to 10.8 μm long and 4.3 to 8.2 μm wide. An alignment of the actin (ACT) and chitin synthase (CHS-1) partial gene sequences showed 100% identity with Colletotrichum spaethianum (Allesch.) Damm, P. F. Cannon & Crous (CBS 167.49). Maximum likelihood analysis was done using the published sequences of the ACT and CHS-1 genes from C. spaethianum and other Colletotrichum species that have curved conidia (Damm et al. 2009; Vieira et al. 2014). The individual data sets were combined using the web tool FaBox (1.41) and analysis with PAUP (1000 bootstrap replicates). Based on morphological characteristics and phylogenetic analysis, the isolates were identified as C. spaethianum. The sequences for the isolates obtained in the present study were deposited in GenBank (ACT Accession Nos. KT184300 to KT184302; CHS-1 Accession Nos. KT184303 to KT184305). The cultures were deposited in the Culture Collection of Microorganisms of the National Institute of the Amazonian Research (Instituto Nacional de Pesquisas da Amazônia, INPA) (INPA 2615, 2770, and 2774). Five Welch onion seedlings were sprayed with a conidial suspension (106 conidia/ml) for each isolate and control seedlings were sprayed with sterile water. Plants were covered with plastic bags and maintained at 28°C ± 2°C in a greenhouse and a 12-h photoperiod. Symptoms typical of anthracnose were induced five days postinoculation, and signs of the pathogen were observed at 12 days postinoculation. No symptoms were observed in the control plants. C. spaethianum was reisolated from symptomatic plants, completing Koch’s postulates. C. spaethianum has been described on Hosta sieboldiana in Germany, Lilium sp. in South Korea, Hemerocallis sp. in New Zealand (Damm et al. 2012), Hemerocallis fulva, Hemerocallis citrine, and Peucedanum praeruptorum in China (Yang et al. 2012; Guo et al. 2013), and Hemerocallis flava in Brazil (Vieira et al. 2014). To our knowledge, this is the first report of C. spaethianum on A. fistulosum. © 2016, American Phytopathological Society. All rights reserved

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV

The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.Comment: Submitted to Physics Letters

Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV

A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this paper.Comment: Replaced with published version. Added journal reference and DO