Saturation and shadowing in high-energy proton-nucleus dilepton production

We discuss the inclusive dilepton cross section for proton (quark)-nucleus collisions at high energies in the very forward rapidity region. Starting from the calculation in the quasi-classical approximation, we include low-x evolution effects in the nucleus and predict leading twist shadowing together with anomalous scaling behaviour.Comment: 32 pages, LaTex, 6 figures, a few modifications of the tex

Advances in breast cancer treatment and prevention: preclinical studies on aromatase inhibitors and new selective estrogen receptor modulators (SERMs).

Intensive basic and clinical research over the past 20 years has yielded crucial molecular understanding into how estrogen and the estrogen receptor act to regulate breast cancer and has led to the development of more effective, less toxic, and safer hormonal therapy agents for breast cancer management and prevention. Selective potent aromatase inhibitors are now challenging the hitherto gold standard of hormonal therapy, the selective estrogen-receptor modulator tamoxifen. Furthermore, new selective estrogen-receptor modulators such as arzoxifene, currently under clinical development, offer the possibility of selecting one with a more ideal pharmacological profile for treatment and prevention of breast cancer. Two recent studies in preclinical model systems that evaluate mechanisms of action of these new drugs and suggestions about their optimal clinical use are discussed

Does parton saturation at high density explain hadron multiplicities at LHC?

An addendum to our previous papers in Phys. Lett. B539 (2002) 46 and Phys. Lett. B502 (2001) 51, contributed to the CERN meeting "First data from the LHC heavy ion run", March 4, 2011Comment: 6 pages, contribution to the CERN meeting "First data from the LHC heavy ion run", March 4, 201

Quenching of hadron spectra in media

We determine how the yield of large transverse momentum hadrons is modified due to induced gluon radiation off a hard parton traversing a QCD medium. The quenching factor is formally a collinear- and infrared-safe quantity and can be treated perturbatively. In spite of that, in the $p_\perp$ region of practical interest, its value turns out to be extremely sensitive to large distances and can be used to unravel the properties of dense quark-gluon final states produced in heavy ion collisions. We also find that the standard modelling of quenching by shifting $p_\perp$ in the hard parton cross section by the mean energy loss is inadequate.Comment: 20 pp, 5 eps figure

Quantifying the Effect of Non-Larmor Motion of Electrons on the Pressure Tensor

In space plasma, various effects of magnetic reconnection and turbulence cause the electron motion to significantly deviate from their Larmor orbits. Collectively these orbits affect the electron velocity distribution function and lead to the appearance of the "non-gyrotropic" elements in the pressure tensor. Quantification of this effect has important applications in space and laboratory plasma, one of which is tracing the electron diffusion region (EDR) of magnetic reconnection in space observations. Three different measures of agyrotropy of pressure tensor have previously been proposed, namely, $A\varnothing_e$, $D_{ng}$ and $Q$. The multitude of contradictory measures has caused confusion within the community. We revisit the problem by considering the basic properties an agyrotropy measure should have. We show that $A\varnothing_e$, $D_{ng}$ and $Q$ are all defined based on the sum of the principle minors (i.e. the rotation invariant $I_2$) of the pressure tensor. We discuss in detail the problems of $I_2$-based measures and explain why they may produce ambiguous and biased results. We introduce a new measure $AG$ constructed based on the determinant of the pressure tensor (i.e. the rotation invariant $I_3$) which does not suffer from the problems of $I_2$-based measures. We compare $AG$ with other measures in 2 and 3-dimension particle-in-cell magnetic reconnection simulations, and show that $AG$ can effectively trace the EDR of reconnection in both Harris and force-free current sheets. On the other hand, $A\varnothing_e$ does not show prominent peaks in the EDR and part of the separatrix in the force-free reconnection simulations, demonstrating that $A\varnothing_e$ does not measure all the non-gyrotropic effects in this case, and is not suitable for studying magnetic reconnection in more general situations other than Harris sheet reconnection.Comment: accepted by Phys. of Plasm

Tunable-diode laser absorption spectrometry

Tunable-diode laser absorption spectrometry (TDLAS) affords a number of advantages for atmospheric measurements. It is a universal method, applicable, in principle, to all gases of atmospheric interest. Because of its extremely high spectral resolution it provides unequivocal identification of the target species, with no interferences from other gases. It provides real-time, in situ measurements with time resolutions better than 1 minute. The sensitivity of the current TDLAS system is marginally capable of measuring HO2. This species exists in the troposphere at concentrations which are up to 2 orders of magnitude higher than those of HO and, in addition, is much less susceptible to removal by the surfaces of the instrument and its sampling system. HO2 is an important HO sub x species in its own right but can also give direct information on the HO concentration by virtue of the rapid partitioning between these two species. The addition of the high-frequency modulation technique to the TDLAS system would ensure its ability to measure HO2 under most atmospheric conditions. The ability of the TDLAS to measure hydrogen peroxide (H2O2) in the ambient atmosphere was also demonstrated. H2O2 measurements give a clear indication of HO sub x mixing ratios and are also important as a photolytic source of HO and as an important oxidant for other atmospheric consitituents such as SO2

Gauge invariance and non-constant gauge couplings

It is shown that space-time dependent gauge couplings do not completely break gauge invariance. We demonstrate this in various gauge theories.Comment: 18 page

Contraction of broken symmetries via Kac-Moody formalism

I investigate contractions via Kac-Moody formalism. In particular, I show how the symmetry algebra of the standard 2-D Kepler system, which was identified by Daboul and Slodowy as an infinite-dimensional Kac-Moody loop algebra, and was denoted by ${\mathbb H}_2$, gets reduced by the symmetry breaking term, defined by the Hamiltonian $$H(\beta)= \frac 1 {2m} (p_1^2+p_2^2)- \frac \alpha r - \beta r^{-1/2} \cos ((\phi-\gamma)/2).$$ For this $H (\beta)$ I define two symmetry loop algebras ${\mathfrak L}_{i}(\beta), i=1,2$, by choosing the `basic generators' differently. These ${\mathfrak L}_{i}(\beta)$ can be mapped isomorphically onto subalgebras of ${\mathbb H}_2$, of codimension 2 or 3, revealing the reduction of symmetry. Both factor algebras ${\mathfrak L}_i(\beta)/I_i(E,\beta)$, relative to the corresponding energy-dependent ideals $I_i(E,\beta)$, are isomorphic to ${\mathfrak so}(3)$ and ${\mathfrak so}(2,1)$ for $E0$, respectively, just as for the pure Kepler case. However, they yield two different non-standard contractions as $E \to 0$, namely to the Heisenberg-Weyl algebra ${\mathfrak h}_3={\mathfrak w}_1$ or to an abelian Lie algebra, instead of the Euclidean algebra ${\mathfrak e}(2)$ for the pure Kepler case. The above example suggests a general procedure for defining generalized contractions, and also illustrates the {\em `deformation contraction hysteresis'}, where contraction which involve two contraction parameters can yield different contracted algebras, if the limits are carried out in different order.Comment: 21 pages, 1 figur

A Survey Of Florida Baseball Cases

Florida has long been a hotbed of baseball activity.1 Today, the state is home to two Major League Baseball (“MLB”) teams, fourteen minor league teams, fifteen spring training sites, both of the schools that train future big league umpires, and numerous amateur and youth team