15 research outputs found
MHV Vertices and Scattering Amplitudes in Gauge Theory
The generic googly amplitudes in gauge theory are computed by using the
Cachazo-Svrcek-Witten approach to perturbative calculation in gauge theory and
the results are in agreement with the previously well-known ones. Within this
approach we also discuss the parity transformation, charge conjugation and the
dual Ward identity. We also extend this calculation to include fermions and the
googly amplitudes with a single quark-anti-quark pair are obtained correctly
from fermionic MHV vertices. At the end we briefly discuss the possible
extension of this approach to gravity.Comment: Latex file, 38 pages, 15 figures; v2, minor changes, references
added; v2, minor changes, 2 references adde
MHV Vertices and Fermionic Scattering Amplitudes in Gauge Theory with Quarks and Gluinos
The Cachazo-Svrcek-Witten approach to perturbative gauge theory is extended
to gauge theories with quarks and gluinos. All googly amplitudes with
quark-antiquark pairs and gluinos are computed and shown to agree with the
previously known results. The computations of the non-MHV or non-googly
amplitudes are also briefly discussed, in particular the purely fermionic
amplitude with 3 quark-antiquark pairs.Comment: 41 pages, 21 figures; v2, minor changes, references added;v3, 2
important additions, references adde
The effectiveness of the stabilization/solidification process on the leachability and toxicity of the tannery sludge chromium
[EN] A stabilization/solidification (S/S) process by using cement was applied to tannery sludge in order to find
a safer way of landfilling this waste. The effects of three parameters on the process effectiveness were
analysed in terms of leachate toxicity and chromium retention (%). The parameters studied were the
relative amount of added water (30e50 wt.%), cement (10e60 wt.% in the solid components), and the use
of three different types of cement (clinker with additions of limestone, with additions of limestone and
fly ashes, and with additions of pozzolans). Statistical analysis performed by variance analysis and categorical
multifactorial tests reveals that all the studied parameters significantly influence the effectiveness
of the process. Results showed that chromium retention decreases as the relative amount of
cement and water increases, probably due to additional chromium provided by cement and increased in
the porosity of the mixtures. Leachate toxicity showed the same minimum value for mixtures with 30%
or 40% cement, depending on the type of cement, showing that clinker is the main material responsible
for the process effectiveness, and additives (pozzolans or fly ashes) do not improve it. The volume increase
is lower as less sludge is replaced by cement and the relative amount of water decreases, and for
the cement without additions of fly ashes or pozzolans. Therefore, the latter seems to be the most
appropriate cement in spite of being more expensive. This is due to the fact that the minimum toxicity
value is achieved with a lower amount of cement; and moreover, the volume increase in the mixtures is
lower, minimizing the disposal cost to a landfill.The authors wish to express their gratitude to the tannery facility INCUSA, S.A., to the cement facility CEMEX ESPAĂ‘A, S.A. and
to Carles MartĂnez for his translation assistance.Montañés Sanjuan, MT.; Sánchez Tovar, R.; Roux, MSB. (2014). The effectiveness of the stabilization/solidification process on the leachability and toxicity of the tannery sludge chromium. Journal of Environmental Management. 143:71-79. doi:10.1016/j.jenvman.2014.04.026S717914
Knockdown of zebrafish Nav1.6 sodium channel impairs embryonic locomotor activities
[[abstract]]Although multiple subtypes of sodium channels are expressed in most neurons, the specific contributions of the individual sodium channels remain to be studied. The role of zebrafish Nav1.6 sodium channels in the embryonic locomotor movements has been investigated by the antisense morpholino (MO) knockdown. MO1 and MO2 are targeted at the regions surrounding the translation start site of zebrafish Nav1.6 mRNA. MO3 is targeted at the RNA splicing donor site of exon 2. The correctly spliced Nav1.6 mRNA of MO3 morphants is 6% relative to that of the wild-type embryos. Nav1.6-targeted MO1, MO2 and MO3 attenuate the spontaneous contraction, tactile sensitivity, and swimming in comparison with a scrambled morpholino and mutated MO3 morpholino. No significant defect is observed in the development of slow muscles, the axonal projection of primary motoneurons, and neuromuscular junctions. The movement impairments caused by MO1, MO2, and MO3 suggest that the function of Nav1.6 sodium channels is essential on the normal early embryonic locomotor activities.[[notice]]補ćŁĺ®Śç•˘[[journaltype]]ĺś‹