Monte Carlo Simulations of Star Clusters - IV. Calibration of the Monte Carlo Code and Comparison with Observations for the Open Cluster M67

We outline the steps needed in order to incorporate the evolution of single and binary stars into a particular Monte Carlo code for the dynamical evolution of a star cluster. We calibrate the results against N-body simulations, and present models for the evolution of the old open cluster M67 (which has been studied thoroughly in the literature with N-body techniques). The calibration is done by choosing appropriate free code parameters. We describe in particular the evolution of the binary, white dwarf and blue straggler populations, though not all channels for blue straggler formation are represented yet in our simulations. Calibrated Monte Carlo runs show good agreement with results of N-body simulations not only for global cluster parameters, but also for e.g. binary fraction, luminosity function and surface brightness. Comparison of Monte Carlo simulations with observational data for M67 shows that is possible to get reasonably good agreement between them. Unfortunately, because of the large statistical fluctuations of the numerical data and uncertainties in the observational data the inferred conclusions about the cluster initial conditions are not firm.Comment: 15 pages, 24 figure

Star Clusters

This review concentrates almost entirely on globular star clusters. It emphasises the increasing realisation that few of the traditional problems of star cluster astronomy can be studied in isolation: the influence of the Galaxy affects dynamical evolution deep in the core, and the spectrum of stellar masses; in turn the evolution of the core determines the highest stellar densities, and the rate of encounters. In this way external tidal effects indirectly influence the formation and evolution of blue stragglers, binary pulsars, X-ray sources, etc. More controversially, the stellar density appears to influence the relative distribution of normal stars. In the opposite sense, the evolution of individual stars governs much of the early dynamics of a globular cluster, and the existence of large numbers of primordial binary stars has changed important details of our picture of the dynamical evolution. New computational tools which will become available in the next few years will help dynamical theorists to address these questions.Comment: 10 pages, 3 figures, Te

The Impact of Shame, Self-Criticism and Social Rank on Eating Behaviours in Overweight and Obese Women Participating in a Weight Management Programme

Recent research has suggested that obesity is a stigmatised condition. Concerns with personal inferiority (social rank), shame and self-criticism may impact on weight management behaviours. The current study examined associations between social comparison (shame, self-criticism), negative affect and eating behaviours in women attending a community based weight management programme focused on behaviour change. 2,236 participants of the programme completed an online survey using measures of shame, self-criticism, social comparison, and weight-related affect, which were adapted to specifically address eating behaviour, weight and body shape perceptions. Correlation analyses showed that shame, self-criticism and social comparison were associated with negative affect. All of these variables were related to eating regulation and weight control (p < 0.001). Path analysis revealed that the association of shame, hated-self, and low self-reassurance on disinhibition and susceptibility to hunger was fully mediated by weight-related negative affect, even when controlling for the effect of depressive symptoms (p < 0.050 to p < 0.010). In addition, feelings of inadequacy and unfavourable social comparisons were associated with higher disinhibition and susceptibility to hunger, partially mediated through weight-related negative affect (p = 0.001). These variables were negatively associated with extent of weight loss during programme attendance prior to the survey, while self-reassurance and positive social comparisons were positively associated with the extent of weight loss prior to the survey (p < .050). Shame, self-criticism, and perceptions of inferiority may play a significant role in self-regulation of eating behaviour in overweight people trying to manage their weight

Neonatal hemochromatosis: Long-term experience with favorable outcome

A

Body image distortions in bulimia nervosa: investigating body size overestimation and body size satisfaction by fMRI

BACKGROUND: Body image distortion is a key symptom of eating disorders. In behavioral research two components of body image have been defined: attitudes towards the body and body size estimation. Only few fMRI-studies investigated the neural correlates of body image in bulimia; those are constrained by the lack of a direct distinction between these different body image components. METHODS: The present study investigates the neural correlates of two aspects of the body image using fMRI: satisfaction rating and size estimation of distorted own body photographs in bulimia nervosa patients (15) and controls (16). RESULTS: Patients were less satisfied with their current body shape than controls and preferred to be thinner. The amount of insula activity reflects the pattern of the satisfaction rating for patients and controls. Patients also overestimated their own body size. For control subjects, an activated cluster in lateral occipital cortex was sensitive for body size distortions, whereas bulimic patients did not demonstrate such a modulation. Furthermore, bulimic subjects did not recruit the middle frontal gyrus (MFG) in contrast to controls during the body size estimation task, maybe indicating a reduced spatial manipulation capacity. Therefore, this activation pattern of lateral occipital cortex and MFG might be responsible for body size overestimation in bulimia. CONCLUSIONS: The present results show that bulimic patients exhibit two distinct deficits in body image representations similar to anorectic patients and that specifically associated neuronal correlates can be identified. Concludingly, our study support psychotherapeutic strategies specifically targeting these two aspects of body image distortions

Long-term results of basiliximab induction immunosuppression in pediatric liver transplant recipients

It has been shown that an induction therapy with the monoclonal anti-interleukin-2 receptor antibody basiliximab (Simulect(TM)) is capable to reduce the incidence of acute graft rejection in adult and pediatric liver transplantation (Ltx). However, data on long-term results using basiliximab in children post-Ltx are still pending. Therefore, the objective of our study was to report on the long-term results of basiliximab induction therapy in pediatric liver transplant recipients. A total of 54 children received two single doses of basiliximab in addition to cyclosporine and prednisolone following Ltx. We analyzed the incidence of acute and chronic graft rejection that of post-transplant lymphoproliferative disease (PTLD), and patient and graft survival. The follow-up was 22-46 months. The historical control group (matched controls) consisted of 54 patients treated with a cyclosporine and prednisolone dual therapy. Patient survival was 53 of 54 in the treatment group and 51 of 54 in the controls. One patient was retransplanted in the treatment group vs. three patients in the control group. The incidence of acute graft rejection was 16.6% compared with 53.7% in the control group (p < 0.001), that of chronic rejection was comparable in both groups (one of 54 vs. one of 54). The incidence of steroid resistant rejection was four of 54 vs. six of 54 that of PTLD were one of 54 vs. zero of 54. There were no adverse effects observed, which could be related to the antibody treatment. We conclude that basiliximab provides safe and effective induction immunosuppression in pediatric liver graft recipients. Short- and even long-term results are excellent

Hypogammaglobulinemia in pediatric liver transplant recipients

Hypogammaglobulinemia has been reported after solid organ transplantation in adults, however immunoglobulin replacement [intravenous immunoglobulins (IVIG)] is only necessary in a minority of affected patients. We here present three pediatric patients with severe post-transplant hypogammaglobulinemia following liver transplantation (LTx) receiving a cyclosporine-based standard immunosuppression. Patient 1 was transplanted at the age of 10 months for biliary atresia. Eight weeks post-Ltx the serum IgG was 1.7 g/L. Patient 2 was transplanted at the age of 12 yr for acute liver failure. Four weeks post-Ltx the IgG dropped to 2.6 g/L. Patient 3 was transplanted at the age of 4 months for biliary atresia. Ten weeks post-Ltx severe hypogammaglobulinemia (IgG < 1.48 g/L) was diagnosed during a severe infectious complication. Patients 1 and 3 received a steroid bolus therapy for acute graft rejection. All patients had normal IgG concentrations prior to Ltx and lymphocyte subsets were post-operatively in the normal range. There was no extensive loss of protein by ascites. IGIV were replaced in the three patients monthly without further complications. In two of the patients (1 and 3) IVIG therapy was discontinued 8 and 10 months after Ltx when the immunosuppression has been reduced and serum IgG concentrations were found in the normal range without further immunoglobulin replacement. Severe hypogammaglobulinemia is a rare phenomenon following pediatric LTx and seems to be mainly caused by immunosuppressive drugs, however, the exact underlying mechanisms are unclear. A screening for hypogammaglobulinemia is useful after pediatric LTx, especially in patients with an intensified immunosuppression. Moreover, further immunologic research in affected patients is necessary