Direct Photon Production in 158 AGeV Pb+Pb Collisions

A measurement of direct photon production in Pb+Pb collisions at 158 AGeV has been carried out in the CERN WA98 experiment. The invariant yield of direct photons in central collisions is extracted as a function of transverse momentum in the interval 0.5 < pT < 4 GeV/c. A significant direct photon signal, compared to statistical and systematical errors, is seen at pT > 1.5 GeV/c. The results constitute the first observation of direct photons in ultrarelativistic heavy-ion collisions which could be significant for diagnosis of quark gluon plasma formation.Comment: Talk presented at Nucleus-Nucleus 2000, Strasbourg, Franc

Genetic and environmental influences on human height from infancy through adulthood at different levels of parental education

Genetic factors explain a major proportion of human height variation, but differences in mean stature have also been found between socio-economic categories suggesting a possible effect of environment. By utilizing a classical twin design which allows decomposing the variation of height into genetic and environmental components, we tested the hypothesis that environmental variation in height is greater in offspring of lower educated parents. Twin data from 29 cohorts including 65,978 complete twin pairs with information on height at ages 1 to 69 years and on parental education were pooled allowing the analyses at different ages and in three geographic-cultural regions (Europe, North America and Australia, and East Asia). Parental education mostly showed a positive association with offspring height, with significant associations in mid-childhood and from adolescence onwards. In variance decomposition modeling, the genetic and environmental variance components of height did not show a consistent relation to parental education. A random-effects meta-regression analysis of the aggregate-level data showed a trend towards greater shared environmental variation of height in low parental education families. In conclusion, in our very large dataset from twin cohorts around the globe, these results provide only weak evidence for the study hypothesis.Peer reviewe

Applications of Machine Learning: A Medical Follow Up Study

This paper describes preliminary work that aims to apply some learning strategies to a medical follow-up study. An investigation of the application of three machine learning algorithms1R, FOIL and InductH to identify risk factors that govern the colposuspension cure rate has been made. The goal of this study is to induce a generalised description or explanation of the classification attribute, colposuspension cure rate (completely cured, improved, unchanged and worse) from the 767 examples in the questionnaires. We looked for a set of rules that described which risk factors result in differences of cure rate. The results were encouraging, and indicate that machine learning can play a useful role in large scale medical problem solving. 1 Introduction One of the central problems of the information age is dealing with the enormous amount of raw information that is available. More and more data is being collected and stored in databases or spreadsheets. As the volume incre..

Everolimus for the prevention of allograft rejection and vasculopathy in cardiac-transplant recipients.

Abstract: BACKGROUND: Everolimus, a novel proliferation inhibitor and immunosuppressive agent, may suppress cardiac-allograft vasculopathy. We conducted a randomized, double-blind, clinical trial comparing everolimus with azathioprine in recipients of a first heart transplant. METHODS: A total of 634 patients were randomly assigned to receive 1.5 mg of everolimus per day (209 patients), 3.0 mg of everolimus per day (211 patients), or 1.0 to 3.0 mg of azathioprine per kilogram of body weight per day (214 patients), in combination with cyclosporine, corticosteroids, and statins. The primary efficacy end point was a composite of death, graft loss or retransplantation, loss to follow-up, biopsy-proved acute rejection of grade 3A, or rejection with hemodynamic compromise. RESULTS: At six months, the percentage of patients who had reached the primary efficacy end point was significantly smaller in the group given 3.0 mg of everolimus (27.0 percent, P<0.001) and the group given 1.5 mg of everolimus (36.4 percent, P=0.03) than in the azathioprine group (46.7 percent). Intravascular ultrasonography showed that the average increase in maximal intimal thickness 12 months after transplantation was significantly smaller in the two everolimus groups than in the azathioprine group. The incidence of vasculopathy was also significantly lower in the 1.5-mg group (35.7 percent, P=0.045) and the 3.0-mg group (30.4 percent, P=0.01) than in the azathioprine group (52.8 percent). The rates of cytomegalovirus infection were significantly lower in the 1.5-mg group (7.7 percent, P<0.001) and the 3.0-mg group (7.6 percent, P<0.001) than in the azathioprine group (21.5 percent). Rates of bacterial infection were significantly higher in the 3.0-mg group than in the azathioprine group. Serum creatinine levels were also significantly higher in the two everolimus groups than in the azathioprine group. CONCLUSIONS: Everolimus was more efficacious than azathioprine in reducing the severity and incidence of cardiac-allograft vasculopathy, suggesting that everolimus therapy may alleviate this serious problem