PubMed · 10114849
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P E Dans. 1990. Self-analysis is active process.. https://pubmed.ncbi.nlm.nih.gov/10114849/
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Dramatic changes in patterns of epidemics have been observed throughout this century. For childhood infectious diseases such as measles, the major transitions are between regular cycles and irregular, possibly chaotic epidemics, and from regionally synchronized oscillations to complex, spatially incoherent epidemics. A simple model can explain both kinds of transitions as the consequences of changes in birth and vaccination rates. Measles is a natural ecological system that exhibits different dynamical transitions at different times and places, yet all of these transitions can be predicted as bifurcations of a single nonlinear model.
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Modern neurosurgery has long had a strong laboratory foundation, and much of this tradition can be traced to the Hunterian Neurosurgical Laboratory of the Johns Hopkins Hospital. Founded with the basic goals of investigating the causes and symptoms of disease and establishing the crucial role that surgeons may play in the treatment of disease, the Hunterian laboratory has adhered to these tenets, despite the dramatic changes in neurosurgery that have occurred in the last 100 years. Named for the famous English surgeon John Hunter (1728-1793), the Hunterian laboratory was conceived by William Welch and William Halsted as a special laboratory for experimental work in surgery and pathology. In 1904, Harvey Cushing was appointed by Halsted to direct the laboratory. With the three primary goals of student education, veterinary surgery that stressed surgical techniques, and meticulous surgical and laboratory record-keeping, the laboratory was quite productive, introducing the use of physiological saline solutions, describing the anatomic features and function of the pituitary gland, and establishing the field of endocrinology. In addition, the original development of hanging drop tissue culture, fundamental investigations into cerebrospinal fluid, and countless contributions to otolaryngology by Samuel Crowe all occurred during this "crucible" period. In 1912, Cushing was succeeded by Walter Dandy, whose work on experimental hydrocephalus and cerebrospinal fluid circulation led to the development of pneumoencephalography. The early days of neurosurgery evolved with close ties to general surgery, and so did the Hunterian laboratory. After Dandy began devoting his time to clinical work, general surgeons (first Jay McLean and then, in 1922, Ferdinand Lee) became the directors of the laboratory. Between 1928 and 1942, more than 150 original articles were issued from the Hunterian laboratory; these articles described significant advances in surgery, including pioneering research on calcium metabolism by William MacCallum and Carl Voegtlin and seminal preclinical work by Alfred Blalock and Vivian Thomas that led to the famous "blue baby" operation in 1944. With the introduction of the operating microscope in the 1950s, much of the focus in neurosurgical science shifted from the laboratory to the operating room. The old Hunterian building was demolished in 1956. The Hunterian laboratory for surgical and pathological research was rebuilt on its original site in 1987, and the Hunterian Neurosurgical Laboratory was reestablished in 1991, with a focus on novel treatments for brain tumors. The strong tradition of performing basic research with clinical relevance has continued.