LHC Charge Asymmetry as Constraint on Models for the Tevatron Top Anomaly

The forward-backward asymmetry $A_{FB}^{t\bar t}$ in top quark production at the Tevatron has been observed to be anomalously large by both CDF and D0. It has been suggested that a model with a $W'$ coupling to $td$ and $ub$ might explain this anomaly, and other anomalies in $B$ mesons. Single-top-quark production in this model is large, and arguably in conflict with Tevatron measurements. However the model might still be viable if $A_{FB}^{t\bar t}$ is somewhat smaller than its current measured central value. We show that even with smaller couplings, the model can be discovered (or strongly excluded) at the LHC using the 2010 data sets. We find that a suitable charge-asymmetry measurement is a powerful tool that can be used to constrain this and other sources of anomalous single-top production, and perhaps other new high-energy charge-asymmetric processes.Comment: 25 pages, 4 figures, note adde

Selective self-categorization: Meaningful categorization and the in-group persuasion effect

Research stemming from self-categorization theory (Turner et al., 1987) has demonstrated that individuals are typically more persuaded by messages from their in-group than by messages from the out-group. The present research investigated the role of issue relevance in moderating these effects. In particular, it was predicted that in-groups would only be more persuasive when the dimension on which group membership was defined was meaningful or relevant to the attitude issue. In two studies, participants were presented with persuasive arguments from either an in-group source or an out-group source, where the basis of the in-group/out-group distinction was either relevant or irrelevant to the attitude issue. Participants' attitudes toward the issue were then measured. The results supported the predictions: Participants were more persuaded by in-group sources than out-group sources when the basis for defining the group was relevant to the attitude issue. However, when the defining characteristic of the group was irrelevant to the attitude issue, participants were equally persuaded by in-group and out-group sources. These results support the hypothesis that the fit between group membership and domain is an important moderator of self-categorization effects

Children's use of multiple categorisations in practice in a multicultural setting.

Little is known about whether and how children combine categories of race, ethnicity, language and religion in multicultural settings where more than one of these dimensions is salient. Ethnographic data from a multicultural London primary school found that children usually organised multiple categories congruently (e.g. 'If you're Indian you are Sikh'), despite strong opposition from teachers. This congruent organisation may originate in an undifferentiated experience of categories in the family, and/or represent the best 'fit' with a local population in which categories were correlated. Children used congruent organisation to infer peers' group membership, which may amplify intergroup contrasts

Socioeconomic deprivation, urban-rural location and alcohol-related mortality in England and Wales

Background: Many causes of death are directly attributable to the toxic effects of alcohol and deaths from these causes are increasing in the United Kingdom. The aim of this study was to investigate variation in alcohol-related mortality in relation to socioeconomic deprivation, urban-rural location and age within a national context. Methods: An ecological study design was used with data from 8797 standard table wards in England and Wales. The methodology included using the Carstairs Index as a measure of socioeconomic deprivation at the small-area level and the national harmonised classification system for urban and rural areas in England and Wales. Alcohol-related mortality was defined using the National Statistics definition, devised for tracking national trends in alcohol-related deaths. Deaths from liver cirrhosis accounted for 85% of all deaths included in this definition. Deaths from 1999-2003 were examined and 2001 census ward population estimates were used as the denominators. Results: The analysis was based on 28,839 deaths. Alcohol-related mortality rates were higher in men and increased with increasing age, generally reaching peak levels in middle-aged adults. The 45-64 year age group contained a quarter of the total population but accounted for half of all alcohol-related deaths. There was a clear association between alcohol-related mortality and socioeconomic deprivation, with progressively higher rates in more deprived areas. The strength of the association varied with age. Greatest relative inequalities were seen amongst people aged 25-44 years, with relative risks of 4.73 (95% CI 4.00 to 5.59) and 4.24 (95% CI 3.50 to 5.13) for men and women respectively in the most relative to the least deprived quintiles. People living in urban areas experienced higher alcohol-related mortality relative to those living in rural areas, with differences remaining after adjustment for socioeconomic deprivation. Adjusted relative risks for urban relative to rural areas were 1.35 (95% CI 1.20 to 1.52) and 1.13 (95% CI 1.01 to 1.25) for men and women respectively. Conclusions: Large inequalities in alcohol-related mortality exist between sub-groups of the population in England and Wales. These should be considered when designing public health policies to reduce alcohol-related harm

Supersymmetric Electroweak Corrections to Single Top Quark Production at the Fermilab Tevatron

We have calculated the $O(\alpha_{ew} M_t^2/M_W^2)$ supersymmetric electroweak corrections to single top quark production via $q\bar q' \to t\bar b$ at the Fermilab Tevatron in the minimal supersymmetric model. The supersymmetric electroweak corrections to the cross section are a few percent for $tan \beta> 1$, and can exceed 10% for $tan\beta<1$. The combined effects of SUSY electroweak corrections and the Yukawa corrections can exceed 10% for favorable parameter values, which might be observable at a high-luminosity Tevatron.Comment: 13 pages, 4 figures available at reques

Assimilation of healthy and indulgent impressions from labelling influences fullness but not intake or sensory experience

Background: Recent evidence suggests that products believed to be healthy may be over-consumed relative to believed indulgent or highly caloric products. The extent to which these effects relate to expectations from labelling, oral experience or assimilation of expectations is unclear. Over two experiments, we tested the hypotheses that healthy and indulgent information could be assimilated by oral experience of beverages and influence sensory evaluation, expected satiety, satiation and subsequent appetite. Additionally, we explored how expectation-experience congruency influenced these factors. Results: Results supported some assimilation of healthiness and indulgent ratings—study 1 showed that indulgent ratings enhanced by the indulgent label persisted post-tasting, and this resulted in increased fullness ratings. In study 2, congruency of healthy labels and oral experience promoted enhanced healthiness ratings. These healthiness and indulgent beliefs did not influence sensory analysis or intake—these were dictated by the products themselves. Healthy labels, but not experience, were associated with decreased expected satiety. Conclusions: Overall labels generated expectations, and some assimilation where there were congruencies between expectation and experience, but oral experience tended to override initial expectations to determine ultimate sensory evaluations and intake. Familiarity with the sensory properties of the test beverages may have resulted in the use of prior knowledge, rather than the label information, to guide evaluations and behaviour

Predictive fermion mass matrix ansatzes in non-supersymmetric SO(10) grand unification

We investigate the status of predictive fermion mass ansatzes which make use of the grand unification scale conditions $m_e=m_d/3$, $m_\mu =3m_s$, and $\mid V_{cb}\mid =\sqrt{m_{c}/m_{t}}$ in non-supersymmetric SO(10) grand unification. The gauge symmetry below an intermediate symmetry breaking scale $M_I$ is assumed to be that of the standard model with either one Higgs doublet or two Higgs doublets . We find in both cases that a maximum of 5 standard model parameters may be predicted within $1\sigma$ experimental ranges. We find that the standard model scenario predicts the low energy $\mid V_{cb}\mid$ to be in a range which includes its experimental mid-value 0.044 and which for a large top mass can extend to lower values than the range resulting in the supersymmetric case. In the two Higgs standard model case, we identify the regions of parameter space for which unification of the bottom quark and tau lepton Yukawa couplings is possible at grand unification scale. In fact, we find that unification of the top, bottom and tau Yukawa couplings is possible with the running b-quark mass within the $1\sigma$ preferred range $m_b=4.25\pm 0.1\, GeV$ provided $\alpha_{3c}(M_Z)$ is near the low end of its allowed range. In this case, one may make 6 predictions which include $\mid V_{cb}\mid$ within its $90\%$ confidence limits. However unless the running mass $m_b>4.4\, GeV$, third generation Yukawa coupling unification requires the top mass to be greater thanComment: 30 pages, 8 figures available on request from [email protected], Late

Polarized Single Top Production at Leptonic Colliders from Broken R Parity Interactions Incorporating CP Violation

The contribution from the R parity violating interactions in the associated production of a top quark with a charm antiquark is examined for high energy leptonic colliders. We concentrate on the reactions associated with the semileptonic top decay. A set of characteristic dynamical distributions for the signal events is evaluated and the results contrasted against those from the standard model W-boson pair production background. Next, we turn to a study of a CP-odd observable, associated with the top spin, which leads to an asymmetry in the energy distribution of the emitted charged leptons for the pair of CP-conjugate final states, $b \bar l \nu \bar c$ and $\bar b l \bar \nu c$. A non vanishing asymmetry arises from a CP-odd phase, embedded in the R parity violating coupling constants, through interference terms between the R parity violating amplitudes at both the tree and loop levels.Comment: revtex file. 17 pages. 7 postscript figures. 1 table. The revised version includes an estimate of experimental uncertainties. Submitted to Phys. Rev.

Entropy production rate is maximized in non-contractile actomyosin

The actin cytoskeleton is an active semi-flexible polymer network whose non-equilibrium properties coordinate both stable and contractile behaviors to maintain or change cell shape. While myosin motors drive the actin cytoskeleton out-of-equilibrium, the role of myosin-driven active stresses in the accumulation and dissipation of mechanical energy is unclear. To investigate this, we synthesize an actomyosin material in vitro whose active stress content can tune the network from stable to contractile. Each increment in activity determines a characteristic spectrum of actin filament fluctuations which is used to calculate the total mechanical work and the production of entropy in the material. We find that the balance of work and entropy does not increase monotonically and the entropy production rate is maximized in the non-contractile, stable state of actomyosin. Our study provides evidence that the origins of entropy production and activity-dependent dissipation relate to disorder in the molecular interactions between actin and myosin