Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions

Excess contributions to the free energy due to interfaces occur for many problems encountered in the statistical physics of condensed matter when coexistence between different phases is possible (e.g. wetting phenomena, nucleation, crystal growth, etc.). This article reviews two methods to estimate both interfacial free energies and line tensions by Monte Carlo simulations of simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is based on thermodynamic integration. This method is useful to study flat and inclined interfaces for Ising lattices, allowing also the estimation of line tensions of three-phase contact lines, when the interfaces meet walls (where "surface fields" may act). A generalization to off-lattice systems is described as well. The second method is based on the sampling of the order parameter distribution of the system throughout the two-phase coexistence region of the model. Both the interface free energies of flat interfaces and of (spherical or cylindrical) droplets (or bubbles) can be estimated, including also systems with walls, where sphere-cap shaped wall-attached droplets occur. The curvature-dependence of the interfacial free energy is discussed, and estimates for the line tensions are compared to results from the thermodynamic integration method. Basic limitations of all these methods are critically discussed, and an outlook on other approaches is given

The Emergence of Hospital Federations: An Integration of Perspectives from Organizational Theory

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68464/2/10.1177_107755878704400206.pd

Recoil-α-fission and recoil-α-α-fission events observed in the reaction 48Ca + 243Am

Products of the fusion-evaporation reaction 48Ca + 243Am were studied with the TASISpec set-up at the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. Amongst the detected thirty correlated α-decay chains associated with the production of element Z=115, two recoil-α-fission and five recoil-α-α-fission events were observed. The latter five chains are similar to four such events reported from experiments performed at the Dubna gas-filled separator, and three such events reported from an experiment at the Berkeley gas-filled separator. The four chains observed at the Dubna gas-filled separator were assigned to start from the 2n-evaporation channel 289115 due to the fact that these recoil-α-α-fission events were observed only at low excitation energies. Contrary to this interpretation, we suggest that some of these recoil-α-α-fission decay chains, as well as some of the recoil-α-α-fission and recoil-α-fission decay chains reported from Berkeley and in this article, start from the 3n-evaporation channel 288115

Development of a core descriptor set for Crohn's anal fistula

AIM: Crohn's anal fistula (CAF) is a complex condition, with no agreement on which patient characteristics should be routinely reported in studies. The aim of this study was to develop a core descriptor set of key patient characteristics for reporting in all CAF research. METHOD: Candidate descriptors were generated from published literature and stakeholder suggestions. Colorectal surgeons, gastroenterologists and specialist nurses in inflammatory bowel disease took part in three rounds of an international modified Delphi process using nine-point Likert scales to rank the importance of descriptors. Feedback was provided between rounds to allow refinement of the next ratings. Patterns in descriptor voting were assessed using principal component analysis (PCA). Resulting PCA groups were used to organize items in rounds two and three. Consensus descriptors were submitted to a patient panel for feedback. Items meeting predetermined thresholds were included in the final set and ratified at the consensus meeting. RESULTS: One hundred and thirty three respondents from 22 countries completed round one, of whom 67.0% completed round three. Ninety seven descriptors were rated across three rounds in 11 PCA-based groups. Forty descriptors were shortlisted. The consensus meeting ratified a core descriptor set of 37 descriptors within six domains: fistula anatomy, current disease activity and phenotype, risk factors, medical interventions for CAF, surgical interventions for CAF, and patient symptoms and impact on quality of life. CONCLUSION: The core descriptor set proposed for all future CAF research reflects characteristics important to gastroenterologists and surgeons. This might aid transparent reporting in future studies

Epicardial adipose tissue predicts mortality in incident hemodialysis patients: a substudy of the Renagel in New Dialysis trial

BACKGROUND: Epicardial adipose tissue (EAT) has been described in the general population as an independent risk marker for incident coronary artery disease. In hemodialysis patients, it correlates with other markers of cardiovascular disease, but it is unknown if it is associated with adverse events. METHODS: post hoc analysis of the Renagel in New Dialysis (RIND) patients study, a randomized trial of sevelamer versus calcium-based phosphate binders in 109 incident hemodialysis patients, followed for all-cause mortality for a median of 49.3 months. Patients underwent baseline cardiac computed tomography imaging within 120 days of dialysis initiation. RESULTS: Baseline EAT measurements were available in 95 patients; EAT was positively correlated with age, body mass index, triglycerides, C-reactive protein, coronary artery calcium and aortic calcium, and negatively correlated with systolic and diastolic blood pressure, serum high density lipoprotein (HPL) cholesterol and serum phosphate (all P < 0.05). During follow-up, a total of 27 (28.4%) patients expired [mortality per 1000 patients/year: 95% confidence interval (95% CI) = 77 (64-94)]. Five-year survival rate was 44. 6% (95% CI: 21.1-65.7) and 71.2% (95% CI: 45.95-86.25) in patients with EAT above or below the median, respectively. Each 10 cc increase in EAT volume was associated with a significant 6% increase in the risk of death during follow-up [hazard ratio (HR): 1.060; 95% CI: 1.013-1.109; P-value = 0.012]. CONCLUSIONS: In this subanalysis of a randomized trial, EAT was an independent predictor of mortality in incident hemodialysis patients after ~4 years of follow-up. These hypothesis-generating findings will need confirmatory evidence

A new assessment of the alleged link between element 115 and element 117 decay chains

A novel rigorous statistical treatment is applied to available data (May 9, 2016) from search and spectroscopy experiments on the elements with atomic numbers Z=115 and Z=117. The present analysis implies that the hitherto proposed cross-reaction link between α-decay chains associated with the isotopes 293117 and 289115 is highly improbable