Finite-size behaviour of the microcanonical specific heat

For models which exhibit a continuous phase transition in the thermodynamic limit a numerical study of small systems reveals a non-monotonic behaviour of the microcanonical specific heat as a function of the system size. This is in contrast to a treatment in the canonical ensemble where the maximum of the specific heat increases monotonically with the size of the system. A phenomenological theory is developed which permits to describe this peculiar behaviour of the microcanonical specific heat and allows in principle the determination of microcanonical critical exponents.Comment: 15 pages, 7 figures, submitted to J. Phys.

Characterising New Physics Models by Effective Dimensionality of Parameter Space

We show that the dimension of the geometric shape formed by the phenomenologically valid points inside a multi-dimensional parameter space can be used to characterise different new physics models and to define a quantitative measure for the distribution of the points. We explain a simple algorithm to determine the box-counting dimension from a given set of parameter points, and illustrate our method with examples from different models that have recently been studied with respect to precision flavour observables.Comment: 14 pages, 8 figure

Speeding Up Computer Simulations: The Transition Observable Method

A method is presented which allows for a tremendous speed-up of computer simulations of statistical systems by orders of magnitude. This speed-up is achieved by means of a new observable, while the algorithm of the simulation remains unchanged.Comment: 20 pages, 6 figures Submitted to Phys.Rev.E (August 1999) Replacement due to some minor change

The Impact of a 4th Generation on Mixing and CP Violation in the Charm System

We study D0-D0 mixing in the presence of a fourth generation of quarks. In particular, we calculate the size of the allowed CP violation which is found at the observable level well beyond anything possible with CKM dynamics. We calculate the semileptonic asymmetry a_SL and the mixing induced CP asymmetry eta_fS_f which are correlated with each other. We also investigate the correlation of eta_fS_f with a number of prominent observables in other mesonic systems like epsilon'/epsilon, Br(K_L -> pi0 nu nu), Br(K+ -> pi+ nu nu), Br(B_s ->mu+ mu-), Br(B_d -> mu+ mu-) and finally S_psi phi in the B_s system. We identify a clear pattern of flavour and CP violation predicted by the SM4 model: While simultaneous large 4G effects in the K and D systems are possible, accompanying large NP effects in the B_d system are disfavoured. However this behaviour is not as pronounced as found for the LHT and RSc models. In contrast to this, sizeable CP violating effects in the B_s system are possible unless extreme effects in eta_fS_f are found, and Br(B_s ->mu+ mu-) can be strongly enhanced regardless of the situation in the D system. We find that, on the other hand, S_psi phi > 0.2 combined with the measured epsilon'/epsilon significantly diminishes 4G effects within the D system.Comment: 22 pages, 23 figures, v2 (references added

Microcanonical entropy for small magnetisations

Physical quantities obtained from the microcanonical entropy surfaces of classical spin systems show typical features of phase transitions already in finite systems. It is demonstrated that the singular behaviour of the microcanonically defined order parameter and susceptibility can be understood from a Taylor expansion of the entropy surface. The general form of the expansion is determined from the symmetry properties of the microcanonical entropy function with respect to the order parameter. The general findings are investigated for the four-state vector Potts model as an example of a classical spin system.Comment: 15 pages, 7 figure

Villous Mucinous Cystadenoma of the Appendix in a Postmenopausal Woman

Because a significant number of mucoceles are caused by mucinous cystadenocarcinoma, the authors stress that a general surgeon be consulted in cases of right lower quadrant “dumbbell shaped” abdominal cysts

Public Acceptability in the UK and USA of Nudging to Reduce Obesity: The Example of Reducing Sugar-Sweetened Beverages Consumption.

BACKGROUND: "Nudging"-modifying environments to change people's behavior, often without their conscious awareness-can improve health, but public acceptability of nudging is largely unknown. METHODS: We compared acceptability, in the United Kingdom (UK) and the United States of America (USA), of government interventions to reduce consumption of sugar-sweetened beverages. Three nudge interventions were assessed: i. reducing portion Size, ii. changing the Shape of the drink containers, iii. changing their shelf Location; alongside two traditional interventions: iv. Taxation and v. Education. We also tested the hypothesis that describing interventions as working through non-conscious processes decreases their acceptability. Predictors of acceptability, including perceived intervention effectiveness, were also assessed. Participants (n = 1093 UK and n = 1082 USA) received a description of each of the five interventions which varied, by randomisation, in how the interventions were said to affect behaviour: (a) via conscious processes; (b) via non-conscious processes; or (c) no process stated. Acceptability was derived from responses to three items. RESULTS: Levels of acceptability for four of the five interventions did not differ significantly between the UK and US samples; reducing portion size was less accepted by the US sample. Within each country, Education was rated as most acceptable and Taxation the least, with the three nudge-type interventions rated between these. There was no evidence to support the study hypothesis: i.e. stating that interventions worked via non-conscious processes did not decrease their acceptability in either the UK or US samples. Perceived effectiveness was the strongest predictor of acceptability for all interventions across the two samples. CONCLUSION: In conclusion, nudge interventions to reduce consumption of sugar-sweetened beverages seem similarly acceptable in the UK and USA, being more acceptable than taxation, but less acceptable than education. Contrary to prediction, we found no evidence that highlighting the non-conscious processes by which nudge interventions may work decreases their acceptability. However, highlighting the effectiveness of all interventions has the potential to increase their acceptability.The study was funded by the UK Department of Health Policy Research Programme (Policy Research Unit in Behaviour and Health) (Grant ID: PRUN-0409-10109)This is the final version of the article. It first appeared from the Public Library of Science via http://dx.doi.org/10.1371/journal.pone.015599

Acceptability of financial incentives for breastfeeding: thematic analysis of readers' comments to UK online news reports.

BACKGROUND: Whilst it is recommended that babies are breastfed exclusively for the first six months, many mothers do not maintain breastfeeding for this length of time. Previous research confirms that women and midwives value financial incentives for breastfeeding, but limited research has explored the wider acceptability of these interventions to the general public. This paper examines opinion towards financial incentives for breastfeeding using reader responses to UK on-line media coverage of a study undertaken in this area. METHODS: This study used netnography to undertake a thematic analysis of 3,373 reader comments posted in response to thirteen articles, published in November 2013, which reported findings from a feasibility study of financial incentives for breastfeeding. All articles were published on one of six UK news websites that achieved a monthly audience of at least five million viewers across laptop and desktop computers and mobile devices during April-May 2013. RESULTS: Nine analytical themes were identified, with a majority view that financial incentives for breastfeeding are unacceptable. These themes cover a range of opinions: from negligent parents unable to take responsibility for their own actions; through to psychologically vulnerable members of society who should be protected from coercion and manipulation; to capable and responsible women who can, and should be allowed to, make their own decisions. Many views focused on the immediate costs of the intervention, concluding that this was something that was currently unaffordable to fund (e.g. by the NHS). Others contrasted the value of the incentive against other 'costs' of breastfeeding. There was some consideration of the issue of cost-effectiveness and cost-saving, where the potential future benefit from initial investment was identified. Many commenters identified that financial incentives do not address the many structural and cultural barriers to breastfeeding. CONCLUSIONS: Overall, those commenting on the on-line UK news articles viewed financial incentives for breastfeeding as unacceptable and that alternative, structural, interventions were likely to be more effective. Further consideration of how best to conduct internet-based qualitative research to elicit opinion towards public health issues is required