6 research outputs found
The G0 Experiment: Apparatus for Parity-Violating Electron Scattering Measurements at Forward and Backward Angles
In the G0 experiment, performed at Jefferson Lab, the parity-violating
elastic scattering of electrons from protons and quasi-elastic scattering from
deuterons is measured in order to determine the neutral weak currents of the
nucleon. Asymmetries as small as 1 part per million in the scattering of a
polarized electron beam are determined using a dedicated apparatus. It consists
of specialized beam-monitoring and control systems, a cryogenic hydrogen (or
deuterium) target, and a superconducting, toroidal magnetic spectrometer
equipped with plastic scintillation and aerogel Cerenkov detectors, as well as
fast readout electronics for the measurement of individual events. The overall
design and performance of this experimental system is discussed.Comment: Submitted to Nuclear Instruments and Method
Seed rain in areas with and without bamboo dominance within an urban fragment of the Atlantic Forest
Aspergillus nidulans Septin AspB Plays Pre- and Postmitotic Roles in Septum, Branch, and Conidiophore Development
Members of the septin family of proteins act as organizational scaffolds in areas of cell division and new growth in a variety of organisms. Herein, we show that in the filamentous fungus Aspergillus nidulans, the septin AspB is important for cellular division, branching, and conidiation both pre- and postmitotically. AspB localizes postmitotically to the septation site with an underlying polarity that is evident as cytokinesis progresses. This localization at the septation site is dependent on actin and occurs before the cross-wall is visible. AspB localizes premitotically as a ring at sites of branching and secondary germ tube emergence. It is the only known branch site marker. In addition, AspB is found at several stages during the development of the asexual reproductive structure, the conidiophore. It localizes transiently to the vesicle/metula and metula/phialide interfaces, and persistently to the phialide/conidiospore interface. A temperature-sensitive mutant of AspB shows phenotypic abnormalities, including irregular septa, high numbers of branches, and immature asexual reproductive structures
The G0 experiment: Apparatus for parity-violating electron scattering measurements at forward and backward angles
In the G0 experiment, performed at Jefferson Lab, the parity-violating elastic scattering of electrons from protons and quasi-elastic scattering from deuterons is measured in order to determine the neutral weak currents of the nucleon. Asymmetries as small as 1 part-per-million in the scattering of a polarized electron beam are determined using a dedicated apparatus. It consists of specialized beam monitoring and control systems, a cryogenic hydrogen (or deuterium) target, and a superconducting, toroidal magnetic spectrometer equipped with plastic scintillation and aerogel Cherenkov detectors, as well as fast readout electronics for the measurement of individual events. The overall design and performance of this experimental system is discussed. © 2011 Elsevier B.V. All rights reserved.Articl