506 research outputs found
Fractionalization noise in edge channels of integer quantum Hall states
A theoretical calculation is presented of current noise which is due charge
fractionalization, in two interacting edge channels in the integer quantum Hall
state at filling factor . Because of the capacitive coupling between the
channels, a tunneling event, in which an electron is transferred from a biased
source lead to one of the two channels, generates propagating plasma mode
excitations which carry fractional charges on the other edge channel. When
these excitations impinge on a quantum point contact, they induce low-frequency
current fluctuations with no net average current. A perturbative treatment in
the weak tunneling regime yields analytical integral expressions for the noise
as a function of the bias on the source. Asymptotic expressions of the noise in
the limits of high and low bias are found
Brote de mastitis clĂnica por Corynebacterium spp. y Streptococcus dysgalactiae en cabras en Salta, Argentina
Intramammary infections are a serious problem for goatâs milk production worldwide. Staphylococcus spp.
are the most prevalent pathogens responsible for intramammary infection in small ruminants; however, there
is only little information about goat mastitis in Argentina. The objective of this communication was to describe
an outbreak of clinical mastitis affecting 12 of 24 lactating goats. Corynebacterium spp. and Streptococcus
dysgalactiae were isolated in pure culture from all milk samples. All the clinical isolates were identified by biochemical
tests and subjected to antibiotic susceptibility tests
Contribution to the knowledge of flat bugs from the temperate south america (hemiptera: heteroptera)
New Aradidae findings as localities and provinces are given from Argentina. Mezira regularis Champion is mentioned for the first time for this country. This work includes a result of studied material of Aradidae that belongs to the Museo de La Plata and Fundacion Miguel Lillo (Argentina).Fil: Contreras, Eugenia Fernanda. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Salta; ArgentinaFil: Neder de RomĂĄn, L. E.. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; ArgentinaFil: CoscarĂłn, M. C.. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; Argentin
Contribution to the knowledge of flat bugs from the temperate south america (hemiptera: heteroptera)
New Aradidae findings as localities and provinces are given from Argentina. Mezira regularis Champion is mentioned for the first time for this country. This work includes a result of studied material of Aradidae that belongs to the Museo de La Plata and Fundacion Miguel Lillo (Argentina).Fil: Contreras, Eugenia Fernanda. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Salta; ArgentinaFil: Neder de RomĂĄn, L. E.. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; ArgentinaFil: CoscarĂłn, M. C.. Universidad Nacional de Jujuy. Instituto de BiologĂa de la Altura; Argentin
Current-voltage correlations in interferometers
We investigate correlations of current at contacts and voltage fluctuations
at voltage probes coupled to interferometers. The results are compared with
correlations of current and occupation number fluctuations at dephasing probes.
We use a quantum Langevin approach for the average quantities and their
fluctuations. For higher order correlations we develop a stochastic path
integral approach and find the generating functions of voltage or occupation
number fluctuations. We also derive a generating function for the joint
distribution of voltage or occupation number at the probe and current
fluctuations at a terminal of a conductor. For energy independent scattering we
found earlier that the generating function of current cumulants in
interferometers with a one-channel dephasing or voltage probe are identical.
Nevertheless, the distribution function for voltage and the distribution
function for occupation number fluctuations differ, the latter being broader
than that of former in all examples considered here.Comment: 23 pages, 10 figures, minor changes, additional appendix, added
reference
La gouvernance territoriale au Brésil : les institutions, les faits et les mythes
As anĂĄlises recentes sobre as organizaçÔes e institucionalidades territorializadas tĂȘmdado grande destaque Ă s formas de regulação capitalista do espaço, permitindo abrir areflexĂŁo sobre as diferenças de trajetĂłrias histĂłricas e de tipos de desenvolvimentoendĂłgeno. No Brasil a criação surpreendente de organizaçÔes e instituiçÔes locais sob aforma de conselhos, comitĂȘs, agĂȘncias e consĂłrcios que ultrapassam os limitesmunicipais Ă© parte desse quadro de anĂĄlise da reação local Ă s mudanças globais.Les analyses rĂ©centes des organisations et des institutions territorialisĂ©es mettent en relief les formes de rĂ©gulation capitaliste de lâespace, ce qui permet dâouvrir une rĂ©flexion sur les diffĂ©rentes trajectoires historiques modĂšles de dĂ©veloppement endogĂšne. Au BrĂ©sil la surprenante crĂ©ation dâ organisations et dâinstitutions locales sous la forme de conseils, comitĂ©s, agences et consortiums qui dĂ©passent les limites municipales fait partie de ce cadre dâ analyse de la rĂ©action locale aux changements globaux
Direct interpretation of the X-ray and neutron three-dimensional difference pair distribution functions (3D-ÎPDFs) of yttria-stabilized zirconia
Three-dimensional difference pair distribution functions (3D-ÎPDFs) from X-ray and neutron diffraction experiments are reported for yttria-stabilized zirconia (Zr0.82Y0.18O1.91). A quantitative analysis of the signatures in the three-dimensional difference pair distribution functions is used to establish that oxygen ions neighbouring a vacancy shift by 0.525â
(5)â
Ă
along âš1,â
0,â
0â© towards the vacancy while metal ions neighbouring a vacancy shift by 0.465â
(2)â
Ă
along âš1,â
1,â
1â© away from the vacancy. The neutron 3D-ÎPDF shows a tendency for vacancies to cluster along âšÂœ,â
Âœ,â
Âœâ©, which results in sixfold coordinated metal ions
Fermionic Mach-Zehnder interferometer subject to a quantum bath
We study fermions in a Mach-Zehnder interferometer, subject to a
quantum-mechanical environment leading to inelastic scattering, decoherence,
renormalization effects, and time-dependent conductance fluctuations. Both the
loss of interference contrast as well as the shot noise are calculated, using
equations of motion and leading order perturbation theory. The full dependence
of the shot-noise correction on setup parameters, voltage, temperature and the
bath spectrum is presented. We find an interesting contribution due to
correlations between the fluctuating renormalized phase shift and the output
current, discuss the limiting behaviours at low and high voltages, and compare
with simpler models of dephasing.Comment: 5 pages, 3 figure
Relationship between work rate and oxygen uptake in mitochondrial myopathy during ramp-incremental exercise
We determined the response characteristics and functional correlates of the dynamic relationship between the rate (Δ) of oxygen consumption ( O2) and the applied power output (work rate = WR) during ramp-incremental exercise in patients with mitochondrial myopathy (MM). Fourteen patients (7 males, age 35.4 ± 10.8 years) with biopsy-proven MM and 10 sedentary controls (6 males, age 29.0 ± 7.8 years) took a ramp-incremental cycle ergometer test for the determination of the O2 on-exercise mean response time (MRT) and the gas exchange threshold (GET). The ΔO2/ΔWR slope was calculated up to GET (S1), above GET (S2) and over the entire linear portion of the response (S T). Knee muscle endurance was measured by isokinetic dynamometry. As expected, peak O2 and muscle performance were lower in patients than controls (P O2/ΔWR than controls, especially the S2 component (6.8 ± 1.5 vs 10.3 ± 0.6 mL·min-1·W-1, respectively; P O2/ΔWR (S T) and muscle endurance, MRT-O2, GET and peak O2 in MM patients (P O2/ΔWR below 8 mL·min-1·W-1 had severely reduced peak O2 values (O2) had lower ΔO2/ΔWR (P O2/ΔWR) is typically reduced in patients with MM, being related to increased functional impairment and higher cardiopulmonary stress
Seleção precoce de famĂlias de irmĂŁos-completos de batata.
Clonal selection is the preferred breeding method used in potatoes (Solanum tuberosum L.). However this selection procedure is only efficient for more advanced generations and shows no good results when applied in the seedling up to the second clonal generation. This study assessed the feasibility of selection in early generations of full-sib potato families and compares the selection method among and within families with the combined selection under different selection intensities. Six experiments were conducted from the first (C1) until the third clonal generation (C3). In C1 a randomized complete block design with four replications of 25 plants was used. In the remaining generations RCB was employed with three replications of 10 plants. Genetic variances were lower between families than within families, for all traits, but the heritabilities between families were almost always larger. The expected gains from selection between and within families were superior to gains from the combined selection in any intensity of selection. The selection of families should have weaker intensity than selection among clones within families. The selection of families was more efficient when based on the average of environments
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