Management of Lantana, an invasive alien weed, in forest ecosystems of India

Lantana is one of the world's worst weeds of South American origin that threatens native biodiversity of forest ecosystems across India. It was introduced into India as a garden ornamental and or a biohedge plant in the early part of the 19th century and now it has virtually invaded all the tropical and subtropical regions of India. Although attempts have been made to control Lantana by physical, chemical and biological methods, there is no success either in its control or the prevention of its spread. No effective management strategy is yet available for the containment of this obnoxious alien weed. On the basis of critical assessment of the biological and ecological attributes of Lantana that enabled it to overcome all the existing management practices, we have developed a new management strategy. The new strategy involves (i) its removal by cut rootstock method, (ii) weeding of saplings from beneath the trees used for perching by generalist birds that disperse the seeds throughout their home range and from surface drainage channels originating from the area covered by such trees and (iii) ecological restoration of weed-free landscapes, preferably to the grassland, or forest communities according to the needs of stakeholders to prevent reinvasion of the same species or secondary invasion by another alien species. The new strategy developed has been implemented successfully in demonstration plots of 2-5 hectares at the Corbett Tiger Reserve (Uttarakhand), Kalesar National Park (Haryana) and Satpura Tiger Reserve (Madhya Pradesh). The advantages of the new management strategy over other control methods currently used are: (i) cost effectiveness, (ii) simple and easy to adopt and (iii) ensures successful control of Lantana without using chemicals and exotic biological control agents, and with minimum disturbance of soil

Neutrino Masses and Mixings in a Minimal SO(10) Model

We consider a minimal formulation of SO(10) Grand Unified Theory wherein all the fermion masses arise from Yukawa couplings involving one 126 and one 10 of Higgs multiplets. It has recently been recognized that such theories can explain, via the type-II seesaw mechanism, the large \nu_\mu - \nu_\tau mixing as a consequence of b-tau unification at the GUT scale. In this picture, however, the CKM phase \delta lies preferentially in the second quadrant, in contradiction with experimental measurements. We revisit this minimal model and show that the conventional type-I seesaw mechanism generates phenomenologically viable neutrino masses and mixings, while being consistent with CKM CP violation. We also present improved fits in the type-II seesaw scenario and suggest fully consistent fits in a mixed scenario.Comment: 27 pages, 13 eps figures, revtex4; references added, some minor correction

Investigation of grain orientations of melt-textured HTSC with addition of uranium oxide, Y2O3 and Y2BaCuO5

Local grain orientations were studied in melt-textured YBCO samples processed with various amounts of depleted uranuim oxide (DU) and Y 2O3 by means of electron backscatter diffraction (EBSD) analysis. The addition of DU leads to the formation of Ucontaining nanoparticles (Y2Ba4CuUOx) with sizes of around 200 nm, embedded in the superconducting Y-123 matrix. The orientation of the Y 2BaCuO5 (Y-211) particles, which are also present in the YBCO bulk microstructure, is generally random as is the case in other melttextured Y-123 samples. The presence of Y-211 particles, however, also affects the orientation of the Y-123 matrix in these samples

Constraining Proton Lifetime in SO(10) with Stabilized Doublet-Triplet Splitting

We present a class of realistic unified models based on supersymmetric SO(10) wherein issues related to natural doublet-triplet (DT) splitting are fully resolved. Using a minimal set of low dimensional Higgs fields which includes a single adjoint, we show that the Dimopoulos--Wilzcek mechanism for DT splitting can be made stable in the presence of all higher order operators without having pseudo-Goldstone bosons and flat directions. The \mu term of order TeV is found to be naturally induced. A Z_2-assisted anomalous U(1)_A gauge symmetry plays a crucial role in achieving these results. The threshold corrections to alpha_3(M_Z), somewhat surprisingly, are found to be controlled by only a few effective parameters. This leads to a very predictive scenario for proton decay. As a novel feature, we find an interesting correlation between the d=6 (p\to e^+\pi^0) and d=5 (p\to \nu-bar K+) decay amplitudes which allows us to derive a constrained upper limit on the inverse rate of the e^+\pi^0 mode. Our results show that both modes should be observed with an improvement in the current sensitivity by about a factor of five to ten.Comment: 21 pages LaTeX, 2 figures, Few explanatory sentences and three new references added, minor typos corrected

Quark-Lepton Quartification

We propose that quarks and leptons are interchangeable entities in the high-energy limit. This naturally results in the extension of [SU(3)]^3 trinification to [SU(3)]^4 quartification. In addition to the unbroken color SU(3)_q of quarks, there is now also a color SU(3)_l of leptons which reduces to an unbroken SU(2)_l. We discuss the natural occurrence of SU(2)_l doublets at the TeV energy scale, which leads remarkably to the unification of all gauge couplings without supersymmetry. Proton decay occurs through the exchange of scalar bosons, with a lifetime in the range 10^{34} - 10^{36} years.Comment: 12 pages, 4 figures. Reference adde

Goodness-of-fit tests when parameters are estimated

Several nonparametric goodness-of-fit tests are based on the empirical distribution function. In the presence of nuisance parameters, the tests are generally constructed by first estimating these nuisance parameters. In such a case, it is well known that critical values shift, and the asymptotic null distribution of the test statistic may depend in a complex way on the unknown parameters. In this paper we use bootstrap methods to estimate the null distribution. We shall consider both parametric and nonparametric bootstrap methods. We shall first demonstrate that, under very general conditions, the process obtained by subtracting the population distribution function with estimated parameters from the empirical distribution has the same weak limit as the corresponding bootstrap version. Of course in the nonparametric bootstrap case a bias correction is needed. This result is used to show that the bootstrap method consistently estimates the null distributions of various goodness-of-fit tests. These results hold not only in the univariate case but also in the multivariate setting