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We analyze the advent and development of eight scientific fields from their inception to maturity and map the evolution of their networks of collaboration over time, measured in terms of co-authorship of scientific papers. We show that as a field develops it undergoes a topological transition in its collaboration structure between a small disconnected graph(More)
We analyze the temporal evolution of emerging fields within several scientific disciplines in terms of numbers of authors and publications. From bibliographic searches we construct databases of authors, papers, and their dates of publication. We show that the temporal development of each field, while different in detail, is well described by population(More)
Lung cancer in young adults has been differently described in publications from various regions of the world, in respect of relative incidence, distribution of morphology and stages, and prognosis of the disease. We analysed retrospectively the data from the cancer registry of the Lungenklinik Heckeshorn in Berlin between 1986 and 1995 with regard to this(More)
AIM To determine the value of high-resolution MRI in pleural and chest wall diseases, the normal and pathologic costal pleura and adjacent chest wall between paravertebral and the axillary region were examined with contrast enhanced high-resolution T1-weighted MRI images using a surface coil. MATERIAL AND METHODS Normal anatomy was evaluated in 5 healthy(More)
This study was designed to investigate the effects of the platelet-activating factor (PAF) on the superoxide anion production (O2.) of human alveolar macrophages (AM) from nonsmoking (n = 18) and smoking (n = 30) subjects. Freshly isolated cells were stimulated with (PAF) or with a phorbol ester (phorbol 12-myristate 13 acetate (PMA)). Stimulation with PAF(More)
The population dynamics underlying the diffusion of ideas hold many qualitative similarities to those involved in the spread of infections. In spite of much suggestive evidence this analogy is hardly ever quantified in useful ways. The standard benefit of modeling epidemics is the ability to estimate quantitatively population average parameters, such as(More)
Understanding the behavior of the universe at large depends critically on insights about the smallest units of matter and their fundamental interactions. Inflationary cosmology is a highly successful framework for exploring these interconnections between particle physics and gravitation. Inflation makes several predictions about the present state of the(More)
We propose a practical scheme to use photons from causally disconnected cosmic sources to set the detectors in an experimental test of Bell's inequality. In current experiments, with settings determined by quantum random number generators, only a small amount of correlation between detector settings and local hidden variables, established less than a(More)