Karyotype of a Bagrid catfish, Mystus vittatus, from the freshwater system of Chidambaram, Tamil Nadu, India

Karyological characters of Mystus vittatus (Bagridae) in the freshwater system of Chidambaram were studied by examining metaphase chromosome spreads from the gill tissues. The examination of 149 metaphase spreads prepared from 25 fingerling specimens indicated that the chromosome number of this species was 2n=54 and the arm number was 12 for metacentric, 36 for submetacentric, and 30 for acrocentric type. The prepared karyotypes of this species consisted, of 3 pairs of metacentric (m), 9 pairs of submetacentric (sm) and 15 pairs of acrocentric (a) chromosomes. The chromosome formula can be represented as 2n = 3m + 9sm + 15a. This karyotype is significantly different from same species reported by others. Karyological parameters showed that centrometric index, arm ratio, relative length, and length variation range of chromosome of this fish species are between 14.97-50.00, 1.00-5.68, 3.12-18.48, and 0.60-3.56, respectively. The largest chromosome in this species is a pair of submetacentric chromosomes. Considering the number of chromosomes, it seems likely that M. vittatus, is a diploid origin fish

LCDG4 and DigiSim - Simulation activities at NICADD/NIU

We present two software packages developed to support detector R&D studies for the International Linear Collider. LCDG4 is a full-detector simulator that provides energy deposits from particles traversing the sensitive volumes of the detector. It has been extensively used within the American ILC community, providing data for algorithm development and detector optimization studies. DigiSim models real-life digitization effects, converting the idealized response into simulated detector readout. It has many useful features to improve the realism in modeling detector response. The main characteristics of these two complementary packages are discussed.Comment: 8 pages, 7 figures, submitted to LCWS05 conference proceedings. Uses slac_one.rt

Improvement of Hamstring Flexibility: A Comparison between Two PNF Stretching Techniques

Objective: To determine the effectiveness of two PNF stretching techniques for improving hamstring flexibility and to compare the effectiveness of two PNF stretching techniques (Hold Relax and Contract Relax-Antagonist Contract) for improving hamstring flexibility. Subjects: 45 normal healthy male subjects. Design: A randomised pre-test post-test control group design. Method: The subjects were randomly assigned into three groups each consisting of 15 subjects. Hamstring flexibility for each group was measured using the active knee extension (AKE) test. Subjects of group A were treated with PNF hold relax stretching, whereas the subjects of group B were treated with PNF CRAC technique. The subjects of group C served as control group and were not subjected to any type of stretching. For each experimental group, stretch was performed three times a week for a total training period of three weeks. Results: A repeated-measures analysis of variance (ANOVA) and a Post HOC analysis using Bonferroni comparisons was used to determine and compare the effectiveness of two PNF stretching techniques at the end of 3 weeks of training protocol. The results demonstrated significant improvement in hamstring flexibility for subjects of group B when compared with those of group A (P = 0.03) at the end of three weeks, with improvement ranging from 0.50 to 15.66 degrees of active knee extension ROM at 95 % confidence interval. Conclusion: Both the techniques viz. PNF Hold Relax and PNF-CRAC are almost equal in their clinical effectiveness for improving hamstring flexibility and that either of the techniques may be used in clinical practice for improving hamstring flexibility

LCDG4 and DigiSim – Simulation activities at NICADD/NIU

We present two software packages developed to support detector R&D studies for the International Linear Collider. LCDG4 is a full-detector simulator that provides energy deposits from particles traversing the sensitive volumes of the detector. It has been extensively used within the American ILC community, providing data for algorithm development and detector optimization studies. DigiSim models real-life digitization effects, converting the idealized response into simulated detector readout. It has many useful features to improve the realism in modeling detector response. The main characteristics of these two complementary packages are discussed

MAPMT H7546B anode current response study for ILC SiD muon system prototype

The proposed Silicon Detector (SiD) concept for the ILC has barrel and end cap muon systems. An SiD scintillator based muon system prototype has 256 strips and was constructed from extruded strips, WLS fibers, clear fibers, and multianode photo multiplier tubes (MAPMT) Hamamatsu H7546B. Six MAPMTs were used. As a first step to understand strip output, the response of every anode to a given brightness of light and applied voltage must be measured. For the test, a custom made light source was used. Each MAPMT output was measured independently. The anode currents were measured at constant (green) input light brightness and the same photocathode to anode voltage (800V). The anode currents have a wide spread; for all tubes the maximum value is 5.23 times larger than the minimum value. The MAPMT cross talk was measured for one of the central inputs. The maximum cross talk value is about 4.9%. The average cross talk for the nearest four neighboring channels is 3.9%, for the farthest four is 1%. To assure the reproducibility and repeatability of the measurements, the double reference method was used

Measurement of the parity-violating asymmetry parameter αb and the helicity amplitudes for the decay Λ0b→J/ψ+Λ0 with the ATLAS detector

A measurement of the parity-violating decay asymmetry parameter, αb, and the helicity amplitudes for the decay Λb0→J/ψ(μ+μ-)Λ0(pπ-) is reported. The analysis is based on 1400 Λb0 and Λ¯b0 baryons selected in 4.6  fb-1 of proton-proton collision data with a center-of-mass energy of 7 TeV recorded by the ATLAS experiment at the LHC. By combining the Λb0 and Λ¯b0 samples under the assumption of CP conservation, the value of αb is measured to be 0.30±0.16(stat)±0.06(syst). This measurement provides a test of theoretical models based on perturbative QCD or heavy-quark effective theory.Fil: F. Monticelli.Fil: Atlas Collaboration

MAPMT H7546B Anode Current Response Study for ILC SiD Muon System Prototype

Abstract The proposed Silicon Detector (SiD) concept for the ILC has barrel and end cap muon systems. An SiD scintillator based muon system prototype has 256 strips and was constructed from extruded strips, WLS fibers, clear fibers, and multianode photo multiplier tubes (MAPMT) Hamamatsu H7546B. Six MAPMTs were used. As a first step to understand strip output, the response of every anode to a given brightness of light and applied voltage must be measured. For the test, a custom made light source was used. Each MAPMT output was measured independently. The anode currents were measured at constant (green) input light brightness and the same photocathode to anode voltage (800V). The anode currents have a wide spread; for all tubes the maximum value is 5.23 times larger than the minimum value. The MAPMT cross talk was measured for one of the central inputs. The maximum cross talk value is about 4.9%. The average cross talk for the nearest four neighboring channels is 3.9%, for the farthest four is 1%. To assure the reproducibility and repeatability of the measurements, the double reference method was used

Measurement of the production of a W boson in association with a charm quark in pp collisions at sqrt(s)=7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb^-1 of pp collision data at sqrt(s)=7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96 +0.26 -0.30 at Q^2=1.9 GeV^2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio sigma(W^+ + bar{c})/sigma(W^- + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s-bar{s} quark asymmetry.Fil: ATLAS Collaboration, G. AAd, F. Monticelli, et al. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina. Cern - European Organization For Nuclear Research; Suiz

Search for bottom squarks in pbarp collisions at sqrt(s)=1.8 TeV

We report on a search for bottom squarks produced in pbarp collisions at sqrt(s) = 1.8 TeV using the D0 detector at Fermilab. Bottom squarks are assumed to be produced in pairs and to decay to the lightest supersymmetric particle (LSP) and a b quark with branching fraction of 100%. The LSP is assumed to be the lightest neutralino and stable. We set limits on the production cross section as a function of bottom squark mass and LSP mass.Comment: 5 pages, Latex. submitted 3-12-1999 to PRD - Rapid Communicatio