[Splitting into two lines: The historical development of the analytical and the gas ultracentrifuge]. / Zwei Entwicklungslinien einer Forschungstechnologie: Zur Geschichte der Analytischen Ultrazentrifugen und Gasultrazentrifugen.

In a historical perspective the ultracentrifuge is often taken as perfect example of a research technology according to Shinn and Joerges (Shinn and Joerges 2000, 2002). Research technologies are defined by a generic device, its own metrology and the interstitiality of the historical actors connected with the device. In our paper we give a detailed analysis of the development of the ultracentrifuge and thereby reveal two different lines of development: analytical ultracentrifuges and gas ultra centrifuges used for isotope separation. Surprisingly, we could not find any interstitial and transversal connections for these two lines. The lines end up with two different devices based on two different technical concepts. Moreover, the great majority of the actors stick to one line. These results are in accordance withother authors, who developed the concept of research technologies further and tried to sharpen their definition.

Leukocyte transfusion and the development of the continuous-flow blood cell separator.

The treatment of anemia and thrombocytopenia with allogeneic cell transfusions is an effective and well-developed technology. However, leukocyte replacement transfusion has been frustrated by the physiology of the leukocytes. To achieve effective leukocyte replacement, the continuous-flow centrifugal blood cell separator was developed, and it soon proved to be an important instrument for separation, collection, and transfusion of all the components of the blood. Thus, the continuous-flow centrifugal blood cell separator has become an important instrument in the science of blood collection and transfusion.

Centrifuge "therapy" for psychiatric patients in Germany in the early 1800s.

In 1818, Dr. Ernst Horn (1774-1848) reported miraculous cures for patients suffering from hysteria through the use of centrifuges at the psychiatric wards of the Charit6-Hospital in Berlin during the previous decade. In his book, "Public Account Concerning My 12 years' Service as Second Physician of the Royal Hospital in Berlin, Including Experiences from Hospitals and Mental Institutions," a full description of the indications and methods for treatment of mental illness, including technical data and construction costs for a rotating bed and rotating chair, is given. The rotating bed was turned by a crankshaft connected by ropes to a capstan. Slowing or stopping was achieved by tensing a rope around a wheel near the ceiling. With a diameter of 13 ft, this therapeutic instrument was capable of producing up to 4 to 5 -Gz in the head region. Several hundred patients and many volunteer subjects, including medical doctors, were reported to have been exposed to the rotating devices, along with some miraculous cures. Apart from the ethical problems associated with this type of torturous treatment, the rotating bed could be described as an ancient centrifuge. With the well-documented observations made on this device, the very first description of G-induced biomedical effects, such as shortness of breath and a feeling of oppression and anxiety, was given: These observations were comparable to those made one century later on human centrifuges and in flight.

Cox's chair: 'a moral and a medical mean in the treatment of maniacs'.

Two hundred years ago Joseph Cox published his book on the treatment of insanity. His novel technique was rotating the body in a specially designed chair. Initially modest and later extravagant claims were made for the therapeutic benefit of 'Cox's chair'. It was widely adopted in Europe in the first decades of the nineteenth century, but lost favour thereafter. Its benefits have proved to be scientific rather than medical because it was adopted by students of the senses to investigate vertigo; a century later it re-emerged as the Bárány chair for the clinical assessment of vestibular function. The legacy of Cox's chair, and its related treatment of swinging, are to be found in funfairs throughout the world.

[The short-arm centrifuge: history and possible uses in cosmonautics and health care services]. / Tsentrifuga korotkogo radiusa: istoriia i perspektivy ispol'zovaniia v praktike kosmonavtiki i zdravookhraneniia.

The review has the objective to analyze applicability of short-radius centrifuges (SAC) in clinical practice. Attempts to treat with centrifuges were made already in the XVIIIth century by E. Darwin (1794) and then E. Horn (1818). Positive results were reported but without particulars of the therapeutic courses. Interest in this method was rekindled by initiation of investigations of the centrifuge as a means to counteract the negative effects of microgravity during manned flights to space. The all-round studies of SAC powers at the Institute for Biomedical Problems attested its efficiency in prevention and therapy of the human body deconditioning brought on by simulated microgravity (bed rest, water immersion), in the 80s the method was tested on patients affected with leg ischemi, and complicated reparation of bone fractures. Collaboration of IBMP investigators with clinical doctors (1987) and a series of dedicated investigations (2000) favoured the view that SAC can be successfully used to prevent and treat blood supply disturbances in legs.

Armstrong Lecture: Opening the envelope: the continuing legacy of Maj. Gen. Harry G. Armstrong, USAF, MC (Ret.).

From 1929-1957, Harry Armstrong, M.D., rose from first lieutenant in the U.S. Army to the rank of major general in the U.S. Air Force. He founded the aeromedical research laboratory at Wright Field, Dayton, OH, founded the Central Medical Establishment, England, became command flight surgeon, U.S. 8th Air Force, England, and founded the Department of Space Medicine (1947), Randolph Field, TX, and served as Surgeon General, USAF (1949-54). Armstrong worked throughout his career on the most advanced aeromedical problems and personally directed breakthrough programs for which he received the highest national and international awards. Applying Armstrong-like projections, one can forecast faster, larger aircraft for the coming decades as well as 21st century habitations on the moon and Mars.

Spin doctors: new innovations for centrifugal apheresis.

The preparation of plasma from blood has a long history dating back to the early 1900s when the concept of blood washing replaced the traditional blood letting. Over the next 57 years landmark discoveries such as centrifugal and membrane filtration systems led to different and rapid plasma, solute, and cell separation. These were not singular events but rather events influenced by the converging chemical, physiological, and engineering advances that have characterized the latter half of the 20th century. These events have led to entire new fields of biomedical research. The biotechnology for on-line plasma separation and plasma treatment has opened a new era, expanding the application of extracorporeal technology to modern therapeutic medicine. The association of biochemical or cellular abnormalities with various disease states provides the rationale for therapeutic plasma exchange (the removal of large amounts of patient's plasma, alone or with replacement with crystalloid) and therapeutic cytopheresis (removal of cellular elements). The purpose of this review is to provide a historical picture of the innovative ideas of the spin doctors and their devices, which predate the centrifugal blood and cell separators commonplace to any hospital or blood bank worldwide. The emphasis is to define the historical events and their impacts on the development of centrifugal devices and apheresis technologies.

Centrifuges: their development and use in gravitational biology.

The nature of centrifuges and their use in biological research are reviewed historically. Centrifuges are particularly important to research in gravitational biology because the inertial (centrifugal) forces developed by motion can be combined with gravitation to produce gravitational fields other than Earth gravity. In orbiting satellites centrifuges can provide an on-board 1 g environment. A similarity of results from the orbiting and ground-based 1 g controls will provide an essential assurance that the biological responses to the spacecraft environment are the result of changes in the gravitational field. The relationship of biological responses to gravitational fields greater or less than Earth gravity is considered. However, at present there is insufficient equivalent information to decide whether there is or is not a proportionality of response to fields stronger or weaker than Earth gravity.