Why the angular distribution of the top decay lepton is unchanged by anomalous tbWtbW coupling

We give a simple physical argument to understand the observation that the angular distribution of the top decay lepton depends only on the polarisation of the top and is independent of any anomalous $tbW$ coupling to linear order.Comment: 4 pages, 2 figures. Added a footnote and consequently a few reference

Is a Nuclear Deal with Iran Possible? An Analytical Framework for the Iran Nuclear Negotiations

Varied diplomatic approaches by multiple negotiators over several years have failed to conclude a nuclear deal with Iran. Mutual hostility, misperception, and flawed diplomacy may be responsible. Yet, more fundamentally, no mutually acceptable deal may exist. To assess this possibility, a "negotiation analytic" framework conceptually disentangles two issues: 1) whether a feasible deal exists and 2) how to design the most promising process to achieve one. Focusing on whether a "zone of possible agreement" exists, a graphical negotiation analysis precisely relates input assumptions about the parties' interests, their no-deal options, and possible deals. Under a plausible, mainstream set of such assumptions, the Iranian regime's no-deal options, at least through summer 2012, appear superior to potential nuclear agreements. If so, purely tactical and process-oriented initiatives will fail. Opening space for a mutually acceptable nuclear deal—that avoids both military conflict and a nuclear-armed or nuclear-capable Iran—requires relentlessly and creatively worsening Iran's no-deal options while enhancing the value to Iranian regime of a "yes." Downplaying both coercive options and upside potential, as international negotiators have often done, works against this integrated strategy. If this approach opens a zone of possible agreement, sophisticated negotiation will be key to reaching a worthwhile agreement

A Multi-Criteria Portfolio Analysis of Hedge Fund Strategies

This paper features a tri-criteria analysis of Eurekahedge fund data strategy index data. We use nine Eurekahedge equally weighted main strategy indices for the portfolio analysis. The tri-criteria analysis features three objectives: return, risk and dispersion of risk objectives in a Multi-Criteria Optimisation (MCO) portfolio analysis. We vary the MCO return and risk targets and contrast the results with four more standard portfolio optimisation criteria, namely the tangency portfolio (MSR), the most diversi_ed portfolio (MDP), the global minimum variance portfolio (GMW), and portfolios based on minimising expected shortfall (ERC). Backtests of the chosen portfolios for this hedge fund data set indicate that the use of MCO is accompanied by uncertainty about the a priori choice of optimal parameter settings for the decision criteria. The empirical results do not appear to outperform more standard bi-criteria portfolio analyses in the backtests undertaken on our hedge fund index data

Subducting slab ultra-slow velocity layer coincident with silent earthquakes in southern Mexico

Great earthquakes have repeatedly occurred on the plate interface in a few shallow-dipping subduction zones where the subducting and overriding plates are strongly locked. Silent earthquakes (or slow slip events) were recently discovered at the down-dip extension of the locked zone and interact with the earthquake cycle. Here, we show that locally observed converted SP arrivals and teleseismic underside reflections that sample the top of the subducting plate in southern Mexico reveal that the ultra-slow velocity layer (USL) varies spatially (3 to 5 kilometers, with an S-wave velocity of ~2.0 to 2.7 kilometers per second). Most slow slip patches coincide with the presence of the USL, and they are bounded by the absence of the USL. The extent of the USL delineates the zone of transitional frictional behavior

Formulation and development of orodispersible sustained release tablet of domperidone

Commercially available domperidone orodispersible tablets (ODT) are intended for immediate release of the drug, but none of them have been formulated for sustained action. The aim of the present research work was to develop and evaluate orodispersible sustained release tablet (ODT-SR) of domperidone, which has the convenience of ODT and benefits of controlled release product combined in one. The technology comprised of developing sustained release microspheres (MS) of domperidone, followed by direct compression of MS along with suitable excipients to yield ODT-SR which rapidly disperses within 30 seconds and yet the dispersed MS maintain their integrity to have a sustained drug release. The particle size of the MS was optimized to be less than 200 μm to avoid the grittiness in the mouth. The DSC thermograms of MS showed the absence of drug-polymer interaction within the microparticles, while SEM confirmed their spherical shape and porous nature. Angle of repose, compressibility and Hausner's ratio of the blend for compression showed good flowability and high percent compressibility. The optimized ODT-SR showed disintegration time of 21 seconds and matrix controlled drug release for 9 h. In-vivo pharmacokinetic studies in Wistar rats showed that the ODT-SR had a prolonged MRT of 11.16 h as compared 3.86 h of conventional tablet. The developed technology is easily scalable and holds potential for commercial exploitation

The Patient's Guide to Psoriasis Treatment. Part 4: Goeckerman Therapy.

BackgroundThe Goeckerman regimen remains one of the oldest, most reliable treatment options for patients with moderate to severe psoriasis. Goeckerman therapy currently consists of exposure to ultraviolet B light and application of crude coal tar. The details of the procedure can be confusing and challenging to understand for the first-time patient or provider.ObjectiveTo present a freely available online guide and video on Goeckerman treatment that explains the regimen in a patient-oriented manner.MethodsThe Goeckerman protocol used at the University of California-San Francisco Psoriasis and Skin Treatment Center as well as available information from the literature were reviewed to design a comprehensive guide for patients receiving Goeckerman treatment.ResultsWe created a printable guide and video resource that covers the supplies needed for Goeckerman regimen, the treatment procedure, expected results, how to monitor for adverse events, and discharge planning.ConclusionThis new resource is beneficial for prospective patients planning to undergo Goeckerman treatment, healthcare providers, and trainees who want to learn more about this procedure. Online media and video delivers material in a way that is flexible and often familiar to patients

Volatility Spillover and Multivariate Volatility Impulse Response Analysis of GFC News Events

This paper applies two measures to assess spillovers across markets: the Diebold Yilmaz (2012) Spillover Index and the Hafner and Herwartz (2006) analysis of multivariate GARCH models using volatility impulse response analysis. We use two sets of data, daily realized volatility estimates taken from the Oxford Man RV library, running from the beginning of 2000 to October 2016, for the S&P500 and the FTSE, plus ten years of daily returns series for the New York Stock Exchange Index and the FTSE 100 index, from 3 January 2005 to 31 January 2015. Both data sets capture both the Global Financial Crisis (GFC) and the subsequent European Sovereign Debt Crisis (ESDC). The spillover index captures the transmission of volatility to and from markets, plus net spillovers. The key difference between the measures is that the spillover index captures an average of spillovers over a period, whilst volatility impulse responses (VIRF) have to be calibrated to conditional volatility estimated at a particular point in time. The VIRF provide information about the impact of independent shocks on volatility. In the latter analysis, we explore the impact of three different shocks, the onset of the GFC, which we date as 9 August 2007 (GFC1). It took a year for the financial crisis to come to a head, but it did so on 15 September 2008, (GFC2). The third shock is 9 May 2010. Our modelling includes leverage and asymmetric effects undertaken in the context of a multivariate GARCH model, which are then analysed using both BEKK and diagonal BEKK (DBEKK) models. A key result is that the impact of negative shocks is larger, in terms of the effects on variances and covariances, but shorter in duration, in this case a difference between three and six months

Structure of the Catalytic Chain of Methanococcus Jannaschii Aspartate Transcarbamoylase in a Hexagonal Crystal Form: Insights into the Path of Carbamoyl Phosphate to the Active Site of the Enzyme

Crystals of the catalytic chain of Methanococcus jannaschii aspartate transcarbamoylase (ATCase) grew in the presence of the regulatory chain in the hexagonal space group P6322, with one monomer per asymmetric unit. This is the first time that crystals with only one monomer in the asymmetric unit have been obtained; all known structures of the catalytic subunit contain several crystallographically independent monomers. The symmetry-related chains form the staggered dimer of trimers observed in the other known structures of the catalytic subunit. The central channel of the catalytic subunit contains a sulfate ion and a K+ ion as well as a glycerol molecule at its entrance. It is possible that it is involved in channeling carbamoyl phosphate (CP) to the active site of the enzyme. A second sulfate ion near Arg164 is near the second CP position in the wild-type Escherichia coli ATCase structure complexed with CP. It is suggested that this position may also be in the path that CP takes when binding to the active site in a partial diffusion process at 310 K. Additional biochemical studies of carbamoylation and the molecular organization of this enzyme in M. jannaschii will provide further insight into these points

A Non-Parametric and Entropy Based Analysis of the Relationship between the VIX and S&P 500

This paper features an analysis of the relationship between the S&P 500 Index and the VIX using daily data obtained from both the CBOE website and SIRCA (The Securities Industry Research Centre of the Asia Pacific). We explore the relationship between the S&P 500 daily continuously compounded return series and a similar series for the VIX in terms of a long sample drawn from the CBOE running from 1990 to mid 2011 and a set of returns from SIRCA's TRTH datasets running from March 2005 to-date. We divide this shorter sample, which captures the behaviour of the new VIX, introduced in 2003, into four roughly equivalent sub-samples which permit the exploration of the impact of the Global Financial Crisis. We apply to our data sets a series of non-parametric based tests utilising entropy based metrics. These suggest that the PDFs and CDFs of these two return distributions change shape in various subsample periods. The entropy and MI statistics suggest that the degree of uncertainty attached to these distributions changes through time and using the S&P 500 return as the dependent variable, that the amount of information obtained from the VIX also changes with time and reaches a relative maximum in the most recent period from 2011 to 2012. The entropy based non-parametric tests of the equivalence of the two distributions and their symmetry all strongly reject their respective nulls. The results suggest that parametric techniques do not adequately capture the complexities displayed in the behaviour of these series. This has practical implications for hedging utilising derivatives written on the VIX, which will be the focus of a subsequent study