The Space Flight InvestigationsRecall that the space flight investigation developed by Dr. Blomqvist was designed to examine the cardiovascular consequences of the fluid shift occurs during space flight. This investigation examines what happens to the cardiovascular system during space flight by studying changes in cardiovascular function, heart size, and the cardiac response to exercise. In addition, and equally important, the same measurements are made on the astronauts before they go into space (preflight), while they are sitting on the launch pad, and after they have been in space and have returned to Earth (postflight).The preflight measurements are essential to understand the "Earth-normal" condition of the astronaut. The inflight measurements are taken at different points during the mission and will indicate how quickly or slowly the astronaut's cardiovascular system changes in space. The postflight experiments will reveal how the cardiovascular system has become "weaker" compared with how our body functions on Earth. During the postflight sessions, a stand test is administered to the astronauts to see how well their cardiovascular system supports them in a standing position. Standing up may not seem, at first thought, to be a difficult thing for astronauts to do. However, it is well known that astronauts are usually not able to tolerate prolonged standing immediately after landing. At this time the experience orthostatic intolerance (orthostatic = standing upright, intolerance = unable to handle), characterized by a tendency to faint upon standing. Various cardiovascular measurements are taken to understand the orthostatic intolerance phenomenon more completely. The preflight, inflight, and postflight portions of this experiment were done on two space missions and the results are very interesting. We will review each major measurement set to see the changes in preflight, inflight, and postflight conditions of the body. For each measurement set, we will include information about why the measurements are important, the equipment used to make measurements, the expected results, and the actual results. These measurement sets were designed to study changes in (1 ) central venous pressure, (2) heart chamber size, (3) static leg volume, (4) cardiovascular function during a stand test to examine postflight orthostatic intolerance, and (5) cardiovascular function during exercise to examine inflight changes in exercise capacity. All the results that you will see involve real experimental data. They were actually obtained during the course of preparing for, during, and after the flight of one or more space flight missions. In other words, you are being exposed to the real stuff! Audiences around the world (both scientific audiences and audiences who are not involved in science but who are excited by space flight) have been exposed to this same data and their imaginations have been ignited. Just think, this kind of thing was only in our grandparents' imagination! It is truly now in our reality. However, all this information and knowledge is worthless unless we are able to communicate and share it with the rest of the world. One of the most important parts of being a scientist is being able to present the results of an experiment clearly to other scientists, to students, and to all of us, so that we can learn from it and so that we can help science move forward to new and better ideas and questions. After you review the scientific results presented in each of the next five sections, you will be asked to break into small teams to work on the development of a presentation that members of your team will deliver to your classmates. This activity will be called "Speaking of Space." Each small team will take one of the five sections and develop a plan for presenting the information in a clear and concise way. More directions for this activity will be provided later, but for now, let's look at the actual results of the five different experiment sets from Dr. Blomqvist's space flight experiment.
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