896 research outputs found
Effect of gibberellin on seeded Vitis vinifera with special reference to induction of seedlessness
Application of GA (25-50 ppm) to Ana:b-e-Shahi at prebloom stage decreased the bunch weight and berry number but weight of the berries was increased and up to 29.6% seedless berries were induced. GA sprays (25-50 ppm) at 2-3 days after full lbloom increased the bunch and berry weights but few seedless berries were induced.GA application (50-150 ppm) to Bhokri grape at 10-11 days before full bloom formed more than 90% seedless berries but bunch weights and berry number were reduced. WitJh an additional second spray at 7- 8 days after full bloom, berry size was impmved but bunch weights were still reduced. At 4-5 days before full bloom application of GA, up to 41.4 % seedless berries were induced but bunch and berry weights were a,gain reduced. With another spray at postbloom stage bunch and berry weights were brought to the level of control. In Gros Colman (Pusa) grape, GA application (50-100 ppm) at 5-6 days before full bloom and 2-3 days after full bloom also formed seedless berries but the bunch and berry weights were reduced. IFruit set was also improvP.d at boVh stages of spray. Prebloom GA application (50-150 ppm) to Alamwick grape, produced seedless berries up to 38.29% but ,bunch and berry weights were appreciably decreased. No effect on berry number was noticed.Application of GA (25-75 ppm) at prebloom + posbbloom and postbloom alone decreased the bunch and berry weights and berry number markedly of Bharat Early and Black Hamburg varieties. Toxic effects like shot berry formation and cracking of rachis were noticed. No seedless berries were observed. however, more berries with 1 or 2 seeds were formed at the expense of berries with 3 or 4 seeds. Even GA application at Jow concentrations to these varieties (5-25 ppm) reduced bunch weights and berry number.The differential response of these seeded varieties of Vitis vinifera is attributed to different amounts of growth factors and inhibitors present in them
Differential response of some seeded grape cultivars of Vitis vinifera to gibberellin application
Several seeded cultivar,s of Vitis vinifera varying in seed content and berry size were tested to see their response to GA application. Oultivars with high seed index number and low seed content like Bhokri, Anab-e-Shahi, Gros Colman (Pusa) and Alamwick did not show any toxic effects due to GA application but responded by producing seedless berries and increasing berry weight with prebloom and postbloom application respectively. Alamwick alone, with high seed index number did not respond to GA by increasing the berry weight but it responded by forming seedless berries. Oultivars like Bharat Early, Black Hamburg and Black Muscat with high seed content per berry and low seed index number did not respond to GA by producing seedless berries and increasing berry weight. This differential response of cultivars to exogenous GA is discussed on the basis of physiological differences in the two groups of cultivars
Squeezing in Multivariate Spin Systems
In contrast to the canonically conjugate variates , representing the
position and momentum of a particle in the phase space distributions, the three
Cartesian components, ,, of a spin- system constitute
the mutually non-commuting variates in the quasi-probabilistic spin
distributions. It can be shown that a univariate spin distribution is never
squeezed and one needs to look into either bivariate or trivariate
distributions for signatures of squeezing. Several such distributions result if
one considers different characteristic functions or moments based on various
correspondence rules. As an example, discrete probability distribution for an
arbitrary spin-1 assembly is constructed using Wigner-Weyl and Margenau-Hill
correspondence rules. It is also shown that a trivariate spin-1 assembly
resulting from the exposure of nucleus with non-zero quadrupole moment to
combined electric quadrupole field and dipole magnetic field exhibits squeezing
in cerain cases.Comment: 13 pages, 1 Table, Presented at ICSSUR-05, Franc
Probing scalar particle and unparticle couplings in e+ e- -> t tbar with transversely polarized beams
In searching for indications of new physics scalar particle and unparticle
couplings in e^+ e^- \to t\bar t, we consider the role of transversely
polarized initial beams at e^+ e^- colliders. By using a general relativistic
spin density matrix formalism for describing the particles spin states, we find
analytical expressions for the squared amplitude of the process with t or \bar
t polarization measured, including the anomalous coupling contributions. Thanks
to the transversely polarized initial beams these contributions are first order
anomalous coupling corrections to the Standard Model (SM) contributions. We
present and analyse the main features of the SM and anomalous coupling
contributions. We show how differences between SM and anomalous coupling
contributions provide means to search for anomalous coupling manifestations at
future e^+ e^- linear colliders.Comment: 28 pages in LaTeX, including 7 encapsulated PostScript figures,
published versio
Effects of Possible Transitions in Neutral Meson Decays}
We explore the possibility that the existing data on like-sign dileptons at
the resonance consist of events arising from mixing and also from transitions. The
consequences of these nonstandard transitions for certain time-asymmetries
which are likely to be measured at the factories are studied.Comment: {\LARGE \bf 10 pages, no figures, process using latex, TIFR/TH/93-5
The role of science in physical natural hazard assessment : report to the UK Government by the Natural Hazard Working Group
Following the tragic Asian tsunami on 26 December 2004, the Prime Minister asked
the Government’s Chief Scientific Adviser, Sir David King, to convene a group of
experts (the Natural Hazard Working Group) to advise on the mechanisms that could
and should be established for the detection and early warning of global physical
natural hazards.
2. The Group was asked to examine physical hazards which have high global or regional
impact and for which an appropriate early warning system could be put in place. It
was also asked to consider the global natural hazard frameworks currently in place
and under development and their effectiveness in using scientific evidence; to
consider whether there is an existing appropriate international body to pull together
the international science community to advise governments on the systems that need
to be put in place, and to advise on research needed to fill current gaps in knowledge.
The Group was asked to make recommendations on whether a new body was
needed, or whether other arrangements would be more effective
CP Violation and Lifetime Differences of Neutral B Mesons from Correlated B^0-B^0bar Pairs
We present a technique to determine the CP violating phases, as well as, the
lifetime differences of the mass eigenstates for both and , by
considering correlated pairs produced at the resonances.
We do not require a detailed time dependent study, but only partial time
integrated rates, with the tag time, either preceding or following the decay of
the other meson to a final state f. f may be a CP eigenstate or a non-CP
eigenstate.Comment: 11 Pages Revte
Detecting new physics contributions to the D0-D0bar mixing through their effects on B decays
New physics effects may yield a detectable mass difference in the D0-D0bar
system, Delta m_D. Here we show that this has an important impact on some B -->
D decays. The effect involves a new source of CP violation, which arises from
the interference between the phases in the B --> D decays and those in the
D0-D0bar system. This interference is naturally large. New physics may well
manifest itself through Delta m_D contributions to these B decays.Comment: 10 pages, Revtex, no figures. To appear in PR
A model for decoherence of entangled beauty
In the context of the entangled state produced at the
resonance, we consider a modification of the usual
quantum-mechanical time evolution with a dissipative term, which contains only
one parameter denoted by and respects complete positivity. In this
way a decoherence effect is introduced in the time evolution of the 2-particle
state, which becomes stronger with increasing distance between
the two particles. While our model of time evolution has decoherence for the
2-particle system, we assume that, after the decay of one of the two B mesons,
the resulting 1-particle state obeys the purely quantum-mechanical time
evolution. From the data on dilepton events we derive an upper bound on
. We also show how is related to the so-called ``decoherence
parameter'' , which parameterizes decoherence in neutral flavoured
meson--antimeson systems.Comment: 11 pages, revtex. Two references and some comments added, version to
be published in Phys. Rev.
Prepotential formulation of SU(3) lattice gauge theory
The SU(3) lattice gauge theory is reformulated in terms of SU(3) prepotential
harmonic oscillators. This reformulation has enlarged gauge invariance under which the prepotential operators transform
like matter fields. The Hilbert space of SU(3) lattice gauge theory is shown to
be equivalent to the Hilbert space of the prepotential formulation satisfying
certain color invariant Sp(2,R) constraints. The SU(3) irreducible prepotential
operators which solve these Sp(2,R) constraints are used to construct SU(3)
gauge invariant Hilbert spaces at every lattice site in terms of SU(3) gauge
invariant vertex operators. The electric fields and the link operators are
reconstructed in terms of these SU(3) irreducible prepotential operators. We
show that all the SU(3) Mandelstam constraints become local and take very
simple form within this approach. We also discuss the construction of all
possible linearly independent SU(3) loop states which solve the Mandelstam
constraints. The techniques can be easily generalized to SU(N).Comment: 25 pages, 10 figures, LaTeX, Minor modifications done. Version to
appear in J. Phys. A: Mathematical and General, 43 (2010
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