Word: iridium
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Dates: during 1970-1979
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...enduring mystery-and created a scientific parlor game. Hypotheses abound to explain the extinction. Brains too small in bodies too large? Emerging mammals feasting on dinosaur eggs? Now comes evidence for another possibility. Geologist Walter Alvarez, probing an ocean canyon near Gubbio, Italy, discovered an abrupt increase in iridium in a limestone layer dating back to the dinosaurs' demise. Probable cause: some mysterious, still unfathomable extraterrestrial event...
...provide a rare, undisturbed record of reversals in the earth's magnetic field. Such fluctuations can influence climate, and possibly allow more cosmic radiation to assail the earth's atmosphere. One layer, only a centimeter thick and tracing back 65 million years, showed a sharp excess of iridium, an element 1,000 times more plentiful in otherworldly matter than in the earth's crust. The "spike" in the readings made a sobering point. "It's the first experimental evidence that something quite extraordinary happened then," says Physics Nobel Laureate Luis Alvarez, who gave...
...first a post-mortem study yielded no poison. But what doctors did find under Markov's skin was a tiny platinum-iridium pellet, 1.7 mm in diameter, with two holes, each a mere .4 mm wide, drilled in at right angles. The holes could have contained a toxic substance, either bacterial or chemical?quite possibly not traceable...
Typically, the physician pushes several hollow steel needles horizontally into the breast through the tumorous area and out the other side (see diagram). Thin plastic tubes are then threaded through the needles (which are subsequently removed) and anchored in place by small plastic buttons at either end. The iridium-in the form of tiny "seeds" embedded in a thin, stiff nylon ribbon -is inserted into the tubes. The outer layer of the seed is a steel sheathing; it blocks dangerous ionizing beta rays (electrons), but allows the escape of the high-energy gamma rays that destroy the tumor...
...Syed, who has been doing implants at the Los Angeles County-University of Southern California Medical Center since 1973, says that a year or more after their treatment, 23 out of 24 patients showed no recurrence of breast cancer. In France, where he has treated some 500 women with iridium implants since 1961, Dr. Bernard Pierquin of Henri Mondor Hospital in the Paris suburb of Créteil reports a survival rate of about 75% to 80% after ten years-comparable to the results of radical mastectomies...