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At least 109 records · Page 6Linked to original sources
PubMed2003

Control of metabolic energy by space systems. Part 1: theoretical reports of space flow structure and function.

In past papers, a notion emerged that space had elements common to the energy of atomic shells to which it could flow by paths to control metabolic energy of animate systems. This paper examines several authors on the structure and function of space energy wave bundle flows seeking mechanisms for metabolic control. The application of time to these waves provides two compartments, time symmetric and time asymmetric, respectively imaginary and real, in a sensitively balanced state as part of a specific system from space to orbits. Disturbance to the balance, where minimal, results in a reflection outside the system to the heat bath consistent with physiology. Arbitrarily more than minimal, results in pathology. A black-hole-like monitor maintains the balance in alliance with a multi-system space stream, the meridian of traditional Chinese medicine. This macroscopic state is now consistent with manipulation using conventional electronics, by way of remedy.

Animals↗
PubMedDate not supplied

Localization of fluorescence spots with space-space MUSIC for mammographylike measurement systems.

Breast cancer diagnosis may be improved by optical fluorescence imaging techniques in the near-infrared wavelength range. We have shown that the recently proposed space-space MUSIC (multiple signal classification) algorithm allows the 3-D localization of focal fluorophore-tagged lesions in a turbid medium from 2-D fluorescence data obtained from laser excitations at different positions. The data are assumed to be measured with two parallel planar sensor arrays on the top and bottom of the medium. The laser sources are integrated at different positions in one of the planes. The space-space data are arranged into an MxN matrix (M, number of sensors; N, number of excitation sources). A singular-value decomposition (SVD) of this matrix yields the detectable number of spot regions with linearly independent behavior with respect to the laser excitation positions and thus allows definition of a signal subspace. Matches between this signal subspace and data from model spots are tested at scanned points in a model medium viewed as the breast region under study. The locations of best matches are then considered the centers of gravity of focal lesions. The optical model used was unbounded and optically homogeneous. Nevertheless, simulated spots in bounded, inhomogeneous media modeling the breast could be localized accurately.

Algorithms↗
PubMed1984

Computed tomography of the carotid space and related cervical spaces. Part II: Neurogenic tumors.

Fourteen neurogenic tumors of the neck were examined with computed tomography (CT) and, in ten cases, angiography. Schwannomas and paragangliomas occurred in the carotid space. These tumors could be distinguished on CT from those occurring more anteriorly, in relation to the parapharyngeal space, and more posteriorly, in relation to the paraspinal space. Schwannomas alone occurred in the paraspinal space. Schwannomas were heterogeneously hypodense before contrast enhancement and at least partially hyperdense after contrast enhancement, with displacement of adjacent vessels on CT, and, if they were of vagal origin, anteromedial displacement of the internal carotid artery on angiography. Paragangliomas usually were homogeneously hyperdense after contrast enhancement, with incorporation of adjacent vessels on CT, and, if they were of carotid body origin, lateral displacement of the internal carotid artery on angiography.

Adolescent↗
PubMed1988

Surgery in space. Phase I: Basic surgical principles in a simulated space environment.

The venturing forth of man into space confronts the surgeon with a new weightless environment with which he will inevitably have to contend. In this study operative procedures were performed on 20 rats in a simulated space environment with use of neutral buoyancy in order to identify those factors that could actually or potentially affect operative technique. There are three general areas of difference from normal conditions in simulated microgravity: physical adaptation to gravity deprivation tissue behavior, including bleeding; and the conduct of surgery. Without gravity, the tactile "feel" of objects is changed ("heavy" and "light" are meaningless terms) and proprioception is confused so that there is past pointing and overreaching of movements. Tissue planes tend to separate, and organs float and bob in the operative field, which makes clamping, cutting, and suturing different. Bleeding is a major consideration; surface tension tends to keep venous blood oozing along surfaces, whereas pulsatile arterial blood forms droplets, streamers, and clouds, depending on the force of the bleeding. These factors and others interfere with surgical technique in a number of ways: dispersion of blood obscures the surgeon's vision, sutures become entangled, organs are not stabilized, and instruments float into the operative field. The limitations of comparing neutral buoyancy to the true zero gravity of space are addressed. There is a definite need for further investigation for development of new surgical techniques in preparation for experimental and clinical surgery in space.

Animals↗
PubMed1994

NASA and Russian Space Agency sign agreement for additional Space Shuttle/Mir missions

On December 16, 1993 NASA Administrator Daniel S. Goldin [correction of Golden] and the Russian Space Agency (RSA) director Yuri Koptev signed a protocol agreeing to up to 10 Shuttle flights to Mir with a total of 24 months time aboard Mir for U.S. astronants, a program of scientific and technological research, and the upgrade and extension of the Mir lifetime during the period 1995-1997. This is the first of a three-phase program in human spaceflight cooperation which may culminate in the construction of an international Space Station. This agreement starts joint development of spacecraft environmental control and life support systems and potential common space suit.

Humans↗
PubMed1989

International cooperation in the field of space life sciences: European Space Agency's (ESA) perspectives.

International cooperation in life sciences, as in any other of the space research fields, takes place at two distinct levels: scientist to scientist, or agency to agency. This article is more concerned with the agency to agency level, which involves the arrangements made between two partners for the flying of experiments and/or hardware on space missions. International cooperation is inherent to the European Space Agency (ESA), since it consists of 13 member states (Austria, Belgium, Denmark, France, Ireland, Italy, the Netherlands, Norway, Spain, Sweden, Switzerland, United Kingdom, and West Germany) and one associated member, Finland. ESA also has special cooperative arrangements with Canada. Life sciences research in ESA is carried out within the Microgravity Research Program, an optional program to which member states (in this case all but Austria and Ireland) contribute "a la carte," and receive their "share" accordingly. Therefore, many of the activities are naturally linked to international arrangements within the member states, and also to arrangements between the agencies, with life sciences being the dominant activity between NASA and ESA.

Animals↗
PubMed2001

Medical guidelines for space passengers. Aerospace Medical Association Task Force on Space Travel.

In the foreseeable future, private companies will manufacture space vehicles with a capacity of transporting tourists into low Earth orbit. Because of the stresses of spaceflight, the effects of microgravity, and limited medical care capability, a system of medical clearance is highly recommended for these space tourists. It is our purpose to establish guidelines for use by private businesses, medical providers, and those planning on being a space tourist. Consequently, a Task Force was organized by the Aerospace Medical Association (AsMA) for the purpose of facilitating safety of passengers, fellow passengers, crew, and flight operations. The guidelines are meant to serve only as a template with the full expectation that exceptions might be made with appropriate rationale.

Disability Evaluation↗
PubMed1993

Limitations to the study of man in space in the U.S. space program.

Research on humans conducted during spaceflight is fraught both with great opportunities and great obstacles. The purpose of this paper is to review some of the limitations to research in space in the United States with hope that an informed scientific community may lead to more rapid and efficient solution of these problems. Limitations arise because opportunities to study the same astronauts in well-controlled situations on repeated spaceflights are practically non-existent. Human research opportunities are further limited by the necessity of avoiding simultaneous mutually-interfering experiments. Environmental factors, including diet and other physiological perturbations concomitant with spaceflight, also complicate research design and interpretation. Technical limitations to research methods and opportunities further restrict the development of the knowledge base. Finally, Earth analogues of space travel all suffer from inadequacies. Though all of these obstacles will eventually be overcome, creativity, diligence, and persistence are required to further our knowledge of humans in space.

Humans↗
PubMed1999

MR and Tc-99m HMPAO SPECT images in a case of unusual widening of perivascular spaces (Virchow-Robin spaces).

We report a rare case of unusual widening of perivascular spaces (Virchow-Robin spaces). MR images showed multiple small round cystic areas along the perforating medullary arteries with signal intensity identical to the cerebrospinal fluid predominantly in the right cerebral white matter. Tc-99m HMPAO SPECT images showed no remarkable laterality and no definite ischemic lesion, and the neurological status of the patient was not remarkable. MR was a diagnostic examination and Tc-99m HMPAO SPECT was a useful supplementary examination in the evaluation of this case of unusual widening of Virchow-Robin spaces.

Aged↗
PubMed1981

A review and comparative analysis of the biological damage induced during space flight by HZE particles and space hadrons.

We have studied the somatic and genetic effects of heavy ions (HZE particles) and the very high energy hadrons of space radiation on various organisms ranging in complexity from bacteriophage to man. Experimental data were obtained in space, on high mountains and in a proton accelerator at energies of 76 GeV. In all these experiments local micro- and macroradiational damage was observed. This damage was characterized by severity over large local regions and for the most part was due to cascades of secondary particle bundles resulting from the collision of very high energy space hadrons with atomic nuclei rather than from cellular hits from relatively low energy single HZE particles. At present there does not appear to be any effective way to provide shielding against these cosmic hadrons.

Animals↗
PubMed1989

Space radiation dosimetry with active detections for the scientific program of the second Bulgarian cosmonaut on board the Mir space station.

A dosimetry-radiometry system has been developed at the Space Research Institute of the Bulgarian Academy of Science to measure the fluxes and dose rates on the flight of the second Bulgarian cosmonaut. The dosimetry system is designed for monitoring the different space radiations, such as solar cosmic rays, galactic cosmic rays and trapped particles in the earth radiation belts. The system consists of a battery operated small size detector unit and a "read-write" and telemetry microcomputer unit. The sensitivity of the instrument (3.67 x 10(-8) rad/pulse) permits high resolution measurements of the flux and dose rate along the track of the Mir space station. We report our initial results for the period of the flight between the 7th and 17th June 1988.

Atlantic Ocean↗
PubMedDate not supplied

Space shuttle operations at the NASA Kennedy Space Center: the role of emergency medicine.

The Division of Emergency Medicine at the University of Florida coordinates a unique program with the NASA John F. Kennedy Space Center (KSC) to provide emergency medical support (EMS) for the United States Space Transportation System. This report outlines the organization of the KSC EMS system, training received by physicians providing medical support, logistic and operational aspects of the mission, and experiences of team members. The participation of emergency physicians in support of manned space flight represents another way that emergency physicians provide leadership in prehospital care and disaster management.

Aerospace Medicine↗
PubMed2004

Austrian dose measurements onboard space station MIR and the International Space Station--overview and comparison.

The Atominstitute of the Austrian Universities has conducted various space research missions in the last 12 years in cooperation with the Institute for Biomedical Problems in Moscow. They dealt with the exact determination of the radiation hazards for cosmonauts and the development of precise measurement devices. Special emphasis will be laid on the last experiment on space station MIR the goal of which was the determination of the depth distribution of absorbed dose and dose equivalent in a water filled Phantom. The first results from dose measurements onboard the International Space Station (ISS) will also be discussed. The spherical Phantom with a diameter of 35 cm was developed at the Institute for Biomedical Problems and had 4 channels where dosimeters can be exposed in different depths. The exposure period covered the timeframe from May 1997 to February 1999. Thermoluminescent dosimeters (TLDs) were exposed inside the Phantom, either parallel or perpendicular to the hull of the spacecraft. For the evaluation of the linear energy transfer (LET), the high temperature ratio (HTR) method was applied. Based on this method a mean quality factor and, subsequently, the dose equivalent is calculated according to the Q(LET infinity) relationship proposed in ICRP 26. An increased contribution of neutrons could be detected inside the Phantom. However the total dose equivalent did not increase over the depth of the Phantom. As the first Austrian measurements on the ISS dosimeter packages were exposed for 248 days, starting in February 2001 at six different locations onboard the ISS. The Austrian dosimeter sets for this first exposure on the ISS contained five different kinds of passive thermoluminescent dosimeters. First results showed a position dependent absorbed dose rate at the ISS.

Astronauts↗
PubMed1998

Analysis of water from the Space Shuttle and Mir Space Station by ion chromatography and capillary electrophoresis.

Drinking water and condensate samples collected from the US Space Shuttle and the Russian Mir Space Station are analyzed routinely at the NASA-Johnson Space Center as part of an ongoing effort to verify water quality and monitor the environment of the spacecraft. Water quality monitoring is particularly important for the Mir water supply because approximately half of the water consumed is recovered from humidity condensate. Drinking water on Shuttle is derived from the fuel cells. Because there is little equipment on board the spacecraft for monitoring the water quality, samples collected by the crew are transported to Earth on Shuttle or Soyuz vehicles, and analyzed exhaustively. As part of the test battery, anions and cations are measured by ion chromatography, and carboxylates and amines by capillary electrophoresis. Analytical data from Shuttle water samples collected before and after several missions, and Mir condensate and potable recovered water samples representing several recent missions are presented and discussed. Results show that Shuttle water is of distilled quality, and Mir recovered water contains various levels of minerals imparted during the recovery processes as designed. Organic ions are rarely detected in potable water samples, but were present in humidity condensate samples.

Chromatography, Ion Exchange↗
PubMed1999

Longevity in space; experiment on the life span of Paramecium cell clone in space.

Life span is the most interesting and also the most important biologically relevant time to be investigated on the space station. As a model experiment, we proposed an investigation to assess the life span of clone generation of the ciliate Paramecium. In space, clone generation will be artificially started by conjugation or autogamy, and the life span of the cell populations in different gravitational fields (microgravity and onboard 1 x g control) will be precisely assessed in terms of fission age as compared with the clock time. In order to perform the space experiment including long-lasting culture and continuous measurement of cell division, we tested the methods of cell culture and of cell-density measurement, which will be available in closed environments under microgravity. The basic design of experimental hardware and a preliminary result of the cultivation procedure are described.

Animals↗
PubMed1999

Personal neutron dosimetry in the space station MIR and the Space Shuttle.

A passive neutron dosemeter based on nuclear track detectors and TLD's was used in 1995 and 1997 on the MIR station and in Space Shuttle flights to MIR. As it is equipped with neutron converters and shieldings of different types the track detector system allows the neutron dose equivalent to be determined in rough energy intervals. The results of the measurements on the MIR station and in the Space Shuttle flights are presented and the influence of charged particles in the complex mixed radiation field in space is discussed. Improvements are possible by means of a new active neutron dosemeter which is under development at the PTB. First measurements with a prototype in the high-energy reference fields at CERN are presented and discussed.

Equipment Design↗
PubMed2005

Interaural timing cues do not contribute to the map of space in the ferret superior colliculus: a virtual acoustic space study.

In this study, we used individualized virtual acoustic space (VAS) stimuli to investigate the representation of auditory space in the superior colliculus (SC) of anesthetized ferrets. The VAS stimuli were generated by convolving broadband noise bursts with each animal's own head-related transfer function and presented over earphones. Comparison of the amplitude spectra of the free-field and VAS signals and of the spatial receptive fields of neurons recorded in the inferior colliculus with each form of stimulation confirmed that the VAS provided an accurate simulation of sounds presented in the free field. Units recorded in the deeper layers of the SC responded predominantly to virtual sound directions within the contralateral hemifield. In most cases, increasing the sound level resulted in stronger spike discharges and broader spatial receptive fields. However, the preferred sound directions, as defined by the direction of the centroid vector, remained largely unchanged across different levels and, as observed in previous free-field studies, varied topographically in azimuth along the rostrocaudal axis of the SC. We also examined the contribution of interaural time differences (ITDs) to map topography by digitally manipulating the VAS stimuli so that ITDs were held constant while allowing other spatial cues to vary naturally. The response properties of the majority of units, including centroid direction, remained unchanged with fixed ITDs, indicating that sensitivity to this cue is not responsible for tuning to different sound directions. These results are consistent with previous data suggesting that sensitivity to interaural level differences and spectral cues provides the basis for the map of auditory space in the mammalian SC.

Acoustic Stimulation↗