A New Type of Singularity Theorem

A new type of singularity theorem, based on spatial averages of physical quantities, is presented and discussed. Alternatively, the results inform us of when a spacetime can be singularity-free. This theorem provides a decisive observational difference between singular and non-singular, globally hyperbolic, open cosmological models.Comment: 6 pages, no figures. Contribution to appear in the Proceedings of the Spanish Relativity Meeting ERE-07, "Relativistic Astrophysics and Cosmology

R-Parity Violation and the HERA Events

The excess in high-Q^2 events at HERA is introduced and possible explanations within the framework of R-parity violating supersymmetry are discussed.Comment: LaTeX, 5 pages, 2 figures. Talk presented at the International Workshop on Physics "Beyond the Standard Model: from Theory to Experiment", Valencia, Spain (October 13 - 17, 1997), to appear in the Proceeding

Singlet-Higgs-Boson Signals at Hadron Colliders

Many extensions of the Standard Model include $SU(2)_L \times U(1)_Y$ singlet higgs bosons, $h^0$, and also vectorlike fermions which couple to it. The production and detection possibilities of such singlet neutral scalars at hadron colliders are considered for different scenarios of vectorlike fermions. We find that for some values of masses and couplings, detection at the CERN Large Hadron Collider (LHC) appears to be a distinct possibility, while at the Fermilab Tevatron upgrade the $h^0$ might be observed only in very favourable circumstances.Comment: 35 pages, latex file, figures 2-7 available upon reques

How can we kill cancer cells: insights from the computational models of apoptosis

Cancer cells are widely known to be protected from apoptosis, which is a major hurdle to successful anti-cancer therapy. Over-expression of several anti-apoptotic proteins, or mutations in pro-apoptotic factors, has been recognized to confer such resistance. Development of new experimental strategies, such as in silico modeling of biological pathways, can increase our understanding of how abnormal regulation of apoptotic pathway in cancer cells can lead to tumour chemoresistance. Monte Carlo simulations are in particular well suited to study inherent variability, such as spatial heterogeneity and cell-to-cell variations in signaling reactions. Using this approach, often in combination with experimental validation of the computational model, we observed that large cell-to-cell variability could explain the kinetics of apoptosis, which depends on the type of pathway and the strength of stress stimuli. Most importantly, Monte Carlo simulations of apoptotic signaling provides unexpected insights into the mechanisms of fractional cell killing induced by apoptosis-inducing agents, showing that not only variation in protein levels, but also inherent stochastic variability in signaling reactions, can lead to survival of a fraction of treated cancer cells.Comment: 10 pages; will appear in World Journal of Clinical Oncology (2010

Solar neutrino: Flux, cosmic rays and the 11 year solar cycle

It is shown that the results of maximum likelihood treatment of Monte Carlo simulation with constant production rate of 7.6 SNU and 1.Epsilon SNU are consistent with the constant production rate when the tests of hypotheses (e.g., t-test, sigma squared-test, Wilcoxon-Mann-Whitney test, run test, etc.) are applied to the two groups of data formed from sunspot minimum range and sunspot maximum range, whereas the real data pulsates with the solar activity cycle. It is shown that SN flux-change is in opposition phase to the solar activity cycle and lags behind the latter by about one year. A correlation between SN flux and the cosmic rays is suggested

The Unforeseen Developments Clause in Safeguards under the WTO: Confusions in Compliance

In this article the author explores in detail the “unforeseen developments†requirement in the Agreement on Safeguards under the WTO. The author seeks to answer questions such as whether the requirement (i.e., unforeseen developments must be demonstrated in order for safeguard measures to be justified) is an integral part of the Agreement on Safeguards, and how the subjectivity associated with this requirement contributes to the difficulty of constructing a reasoned and adequate account of the causal chain. The article also includes within its scope a brief analysis of larger issues such as the political and economic rationale behind safeguard measures, and how ambiguities in the Agreement on Safeguards can destabilize the discipline of safeguards and defeat one of its major purposes - to help countries nurture their infant industries. Finally, the article reflects upon how India, being one of the leading users of safeguard measures as of 2008, is likely to be affected by unclear areas in the present legislation such as the unforeseen developments clause.India, international trade, safeguards, unforeseen developments, WTO, Industrial Organization, Institutional and Behavioral Economics, International Development, International Relations/Trade, Political Economy,

Mass bounds for Triplet Scalars of the Left-Right symmetric model and their future detection prospects

The standard formulation of the Left-Right symmetric model involves scalars transforming as a triplet under SU(2)L. This multiplet contains particles which are uncharged, singly-charged, and doubly-charged. We derive a bound on the uncharged scalar mass of 55.4 GeV using results from LEP-II and find that a range upto 110 GeV may be explored at the NLC at the 5sigma level. We also discuss search strategies for the singly- and doubly-charged scalars at the Tevatron and the LHC. Possible Standard Model backgrounds for the relevant modes are estimated and compared with the signal. At the LHC, the prospects of detecting the doubly-charged scalar are bright up to a mass of 850 GeV while the 5sigma discovery limit of the singly-charged mode extends to 240 GeV for an integrated luminosity of 100 inverse fb. At the Tevatron, with an integrated luminosity of 25 inverse fb, the doubly-charged state can be detected if its mass is less than 275 GeV while the reach for the singly charged scalar is 140 GeV.Comment: Latex, References added, some postscript figures modified, to appear in Phys. Rev.