Conjugation-mediated plasmid exchange between bacteria grown under space flight conditions

Mobile genetic elements (MGE) such as phages, plasmids and transposons play a crucial role in bacterial adaptation and evolution. These MGE mobilize and reorganize genes within a given genome or between bacterial cells. The impact of space flight conditions on these processes is largely unknown. The Mobilisatsia/Plasmida experiment was set up to investigate the impact of space flight conditions on plasmid-mediated conjugation. The experiment was done aboard the International Space Station during the Soyuz Mission 8S (April 19th until April 30^th 2004). An experiment was performed with the Gram-positive Bacillus thuringiensis AND931 (carrying the conjugative plasmid pXO 16), B. thuringiensis 4Q7 (with mobilizable plasmid pC194) andB. thuringiensis GBJ002 (final recipient). A second experiment was carried out with the Gram-negative Escherichia coli CM140 (carrying the conjugative plasmid RP4), E. coli CM1962 (with the mobilizable plasmid pMOL222) and Cupriavidus metallidurans AE815 (final recipient). It was observed by selective platings that plasmid exchange between the Gram-positive bacterial strains occurred in the space flight experiment. It is speculated that the latter plasmid exchange occurs more efficient than in the ground control experiment. No significant differences could be observed between space flight and ground control for the Gram-negative bacteria. The data indicate that plasmid exchange between microorganisms is occurring under space flight conditions. Since microorganisms are endogenous to any spacecraft and their presence considered as a possible jeopardy for manned space exploration, more experiments are needed to evaluate the occurrence and implications of microbial adaptation and evolution via MGE.     

Biological dosimetry in the ENEIDE Mission on the International Space Station

Space radiation represents one of the major health hazards to crews of interplanetary missions. As the duration of space flight increases, according to International Space Station (ISS) and Mars mission programs, the risk associated with exposure to ionizing radiation also increases. Although physical dosimetry is routinely performed in manned space missions, it is generally accepted that direct measurement of biological endpoints (biological dosimetry) is necessary for a precise assessment of radiation risk in extraterrestrial activities. Chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBLs) are particularly suitable to this purpose, as they can provide estimates of both equivalent radiation dose and risk. In this study, cytogenetic analysis was performed on PBL chromosomes of an Italian astronaut involved in two different 10-day missions on the ISS (Marco Polo, April 2002, and ENEIDE, May 2005). Blood samples were collected before and after flights. CAs were evaluated in either mitotic spreads or in prematurely condensed chromosomes (PCC) by Fluorescence in Situ Hybridization (FISH). In addition, blood samples were exposed to graded doses of X-rays in vitro before and after the flight and cytogenetic damage evaluated to investigate whether the space environment alters the sensitivity of human cells to ionizing radiation. The yield of baseline chromosomal aberrations was not modified following Marco Polo and ENEIDE mission. This is consistent with the low dose absorbed in these short-term space missions. Preliminary results from Marco Polo mission suggested a significant increase in intrinsic radiosensitivity of lymphocytes after landing compared to pre-flight and follow-up (6 months after landing) samples. However, this effect was not observed during the ENEIDE mission. The results suggest that intra-indi-vidual variations in radiosensitivity are significant, but they cannot be related to the space flight.     

Experiences from a French-German project - on the integration of pupils in an actual space experiment

The German-French biological experiment AQUARIUS-XENO-PUS which flew on the French Soyuz taxi flight Andromède to the International Space Station ISS was extended by an outreach project. Pupils of class 10 to 12, age 16 to 18 years from Ulm/Germany and Tomblaine-Nancy/France were involved in this space experiment. They recorded swimming behavior of Xenopus laevis tadpoles by video. They used this as the 1gground control for similar observations in microgravity exposed tadpoles on the International Space Station, ISS. The pupils were instructed to perform all experimental steps following the protocol of the video recordings on ISS which were done by the French cosmonaut Claudie Haigneré. After the flight, they evaluated swimming activity of both ground controls and space animals using parameters such as type, velocity and acceleration of swimming, or the distribution patterns of tadpoles within the miniaquaria. The pupil project included theoretical components to introduce them to the field of gravitational biology. Nancy pupils established a homepage (www.xenope.com) about background and aim of their scientific project while Ulm pupils received an extended theoretical and practical education about gravity effects on biological systems, what gravity means for life on Earth, and about hardware used for biological research in Space. A feature of the project was the exchange of ideas between all pupils by internet and meetings which took place in Ulm (June 2001), Nancy (February 2002) and Paris (May 2002). Selected pupils presented the work at international conferences on Life Science Research in Space. The project lasted about 18 months; only 1 of 20 participants left the project after 6 months. - We consider our approach as a successful way to include high school students in space experiments on a cheap cost level and to bring the ideas of gravitational biology into curricula of European schools. The project also showed that personal engagement from the teachers and scientists as well as from the supporting agency staff is a prerequisite for the success of co-operations between school and university.     

Future Experiments to Measure Liquid-Gas Phase Change and Heat Transfer Phenomena on the International Space Station

The article presents the approach of the European Space Agency to promote research in weightlessness and in particular onboard the International Space Station. In order to maximize the return on investments, a strong international scientific collaboration is encouraged. These Science Teams support the preparation and utilisation of the flight hardware and exploit the measurement data. In the domain of physical sciences the topics dealt with at the time of writing the present paper cover fundamental physics, fluid physics, material sciences research and specific preparatory studies in anticipation of space exploration missions. The present article focuses on two-phase (liquid-gas phase change) heat transfer related experiments. These activities cover evaporation driven thermocapillary convection, pool- and flow boiling, evaporation and condensation of films together with wettability realted issues on both reference and structured surfaces, and heat pipe systems. Some hardware are in an advanced state of development, the feasibility of some was studied or is under definition at the time of the preparation of this paper. The objectives of the experiments are described together with their expected capabilities. Beyond the understanding of mostly fundamental physical processes, the data of all the described experiments are intended to be used to validate theoretical approaches and numerical tools, which are often developed by the Science Teams in parallel with the the flight hardware design activities of space industry.     

Drosophila GENE Experiment in the Spanish Soyuz Mission to the ISS: II. Effects of the Containment Constraints

In the GENE experiment performed during an 11-day Soyuz Mission to the International Space Station (ISS), we intended to determine if microgravity affects Drosophila metamorphosis processes. Control experiments were performed including a 1g ground control parallel to the ISS flight samples and a Random Position Machine microgravity simulated control. A preliminary analysis of the results indicates that five hundred to one thousand genes change their expression profiles depending on the cut-off levels selected. Especially affected among them are the mitochondrial ones (an example with the respiratory chain is presented). We show here that there is a synergic effect of the constraints introduced to meet the requirements of the space experiment (mainly, a cold step and the use of hermetically closed Type-I containers). The cold transport step to the launch site was introduced to slow down the pupal development. The hermetically closed Type I containers were required to ensure the containment of the fixative (acetone) in the experiment. As shown here, the oxygen concentration inside the container was not optimal but fully compatible with pupal development. It is highly likely that such combined environmental effects will become a common finding in these types of studies as they become more complicated and extensive. They could open the way to understand how the gene expression patterns and the actual phenotypes can adjust to the environment. These findings indicate the importance of a vigorous ground based program in support of real microgravity experiments. Only then we can utilize the ISS in order to understand the consequences of the modified environment in outer space on living organisms.     

Radiation dosimetry for microbial experiments in the International Space Station using different etched track and luminescent detectors

The laboratory of Microbiology at SCK.CEN, in collaboration with different universities, participates in several ESA programmes with bacterial experiments that are carried out in the International Space Station (ISS). The main objective of these programmes is to study the effects of space flight conditions such as microgravity and cosmic radiation on the general behaviour of model bacteria. To measure the radiation doses received by the bacteria, different detectors accompanied the microbiological experiments. The results obtained during two space flight missions are discussed. This dosimetry experiment was a collaboration between different institutes so that the doses could be estimated by different techniques. For measurement of the high linear energy transfer (LET) doses (>10 keV microm(-1)), two types of etched track detectors were used. The low LET part of the spectrum was measured by three types of thermoluminescent detectors ((7)LiF:Mg,Ti; (7)LiF:Mg,Cu,P; Al(2)O(3):C) and by the optically stimulated luminescence technique using Al(2)O(3):C detectors.     

External occulter laboratory demonstrator for the forthcoming formation flying coronagraphs

The design and optimization of the external occulter geometry is one of the most discussed topics among solar coronagraph designers. To improve the performance of future coronagraphs and to stretch their inner fields of view toward the solar limb, the new concept of coronagraphs in formation flight has been introduced in the scientific debate. Solar coronagraphs in formation flight require several mechanical and technological constraints to be met, mainly due to the large dimension of the occulter and to the spacecraft's reciprocal alignment. The occulter edge requires special attention to minimize diffraction while being compatible with the handling and integrating of large delicate space components. Moreover, it is practically impossible to set up a full-scale model for laboratory tests. This article describes the design and laboratory tests on a demonstrator for a coronagraph to be operated in formation flight. The demonstrator is based on the principle of the linear edge, thus the presented results cannot be directly extrapolated to the case of the flying circular occulter. Nevertheless, we are able to confirm the results of other authors investigating on smaller coronagraphs and provide further information on the geometry and tolerances of the optimization system. The described work is one of the results of the ESA STARTIGER program on formation flying coronagraphs ["The STARTIGER's demonstrators: toward a new generation of formation flying solar coronagraphs," in 2010 International Conference on Space Optics (ICSO) (2010), paper 39].     

ENEIDE: An experiment of a spaceborne, L1/L2 integrated GPS/WAAS/EGNOS receiver

The ENEIDE mission consisted of 22 scientific experiments that were carried out on the Soyuz and on the International Space Station (ISS) during the flight of the Soyuz 10S to the ISS in April 2005. Among these experiments there was the ENEIDE instrument, which gave the name to the whole mission. ENEIDE is a space-qualified, dual-frequency, integrated GPS/WAASEGNOS receiver aimed to the verification of the tracking of GPS plus the augmentation systems from space. The receiver is built by Thales Alenia Space-Italia, Milan plant (formerly Laben), on the basis of the space-qualified dual-frequency receiver LAGRANGE, that will be a payload of several ESA and Italian Space Agency missions like ESA’s GOCE or the Italian COSMO SKYMED constellation to cite few examples. This paper addresses the first results of the ENEIDE flight data analysis.     

Gentamicin: effect on E. coli in space

Previous investigations have shown that liquid bacterial cultures grown in space flight were not killed as effectively by antibiotic treatments as were cultures grown on Earth. However, the cause for the decreased antibiotic effectiveness remains unknown. Possible explanations include modified cell proliferation and modified antibiotic transport in the culture medium. Escherichia coli cultures were grown in space flight (STS-69 and STS-73), with and without gentamicin, on a solid agar substrate thus eliminating fluid effects and reducing the unknowns associated with space-flight bacterial cultures in suspension. This research showed that E. coli cultures grown in flight on agar for 24 to 27 hours experienced a heightened growth compared to simultaneous controls. However, addition of gentamicin to the agar killed the bacteria such that both flight and ground control E. coli samples had similar final cell concentrations. Therefore, while the reported existence of a decrease in antibiotic effectiveness in liquid cultures remains unexplained, these data suggest that gentamicin in space flight was at least as effective as, if not more effective than, on Earth, when E. coli cells were grown on agar.     

Seeds-in-space education experiment during the Dutch soyuz mission DELTA

We have used the broad appeal of the universe and space flight to boost interest in science education in The Netherlands via a classroom experiment designated Seeds In Space (SIS). By germinating Rucola seeds in the dark and in the light in ground classrooms and by comparing these results with those obtained in the same experiment performed in the International Space Station (ISS) during the Dutch Soyuz mission DELTA, students could learn about the cues that determine direction of plant growth. This paper describes both the preparations that led up to the SIS experiment as well as the popular and scientific outcome. Within The Netherlands, some 80.000 students participated, representing 15% of the population in the age group of 10-14 years old. In addition, another 80.000 German pupils, a few local schools in the Moscow -Koroljov- area and some in the Dutch Antilles also participated in the SIS experiment. Considering these numbers, it can be concluded that SIS was a very successful educational project and might be considered for future space flight missions.     

Concept for on orbit liquid hydrogen test bed

There is growing interest in the utilization of cryogenic propellants for future space missions. The utilization of these propellants for long duration in space presents substantial challenges in fluid management in the low g environment. Lockheed Martin (LM) is developing the concept for a space borne system for demonstration of long term storage, various fluid management tests involving control of tank pressure, location and identification of vapor and liquid phases, venting in low g, mass gauging, and extension of life with cryocoolers and location of liquid for transfer. In addition the concept includes autonomous coupling and hydrogen transfer from tank to tank. The concept is based on a flight qualified flight proven hydrogen Dewar design from a previous program The concept for this system is described.     

International Heat and Mass Transfer Experiments on the 48th ESA Parabolic Flight Campaign of March 2008

Aircraft parabolic flights provide repetitively up to 20 s of reduced gravity during ballistic flight manoeuvres and are used to conduct short microgravity investigations in Physical and Life Sciences and Technology, to test instrumentation and to train astronauts before a space flight. Their use is complementary to other microgravity platforms, such as drop towers, sounding rockets, automatic orbital capsules and the International Space Station (ISS), and preparatory to space missions. Since 1997, parabolic flights in Europe are performed with the Airbus A300 ‘Zero-G’, the world largest aircraft for this research activity. ESA campaigns are organized at a rate of two campaigns per year, usually in spring and autumn. Depending on their sizes, 12 to 14 experiments can be accommodated per campaign. Due to the scientific interest and the growing importance of heat and mass transfer experiments, ESA has dedicated its 48th ESA parabolic flight campaign of 2008 to this kind of experiments. A certain number of experiments have been identified in Europe, USA and Japan and eight of these experiments have been assigned to the 48th ESA campaign of March 2008. Five other experiments are scheduled to participate in the next 49th ESA campaign of October 2008. The ESA aircraft parabolic flight programme and the Airbus A300 ‘Zero-G’ aircraft are presented. The eight heat and mass transfer experiments foreseen for the 48th campaign of March 2008 are summarized.     

The atmospheric nightglow in the 300–400 nm wavelength Results by the balloon-borne experiment “BABY”

The balloon-borne experiment, named BAckground BYpass (BABY) belongs to a wider program that has as its final goal the detection and study of high-energy cosmic rays from space (satellite, Space Station). An information of fundamental importance for this class of projects concerns the nighttime background light. The instrument designed to detect fluorescence photons is basically composed of two collimated photomultipliers: a single photon-counting PMT and a charge integration PMT. We briefly report the details of the design, operation and performance of the detector, which was designed and completely built at the IFCAI–CNR Institute in Palermo. Preliminary analysis and results of the nocturnal background in the range of 300–400 nm are presented for the whole duration of the flight during the 1998 Mediterranean balloon flight campaign. A substantial part of the flight was at night over the sea.     

Design and qualification of the AMS-02 flight cryocoolers

Four commercial Sunpower M87N Stirling-cycle cryocoolers will be used to extend the lifetime of the Alpha Magnetic Spectrometer-02 (AMS-02) experiment. The cryocoolers will be mounted to the AMS-02 vacuum case using a structure that will thermally and mechanically decouple the cryocooler from the vacuum case. This paper discusses modifications of the Sunpower M87N cryocooler to make it acceptable for space flight applications and suitable for use on AMS-02. Details of the flight model qualification test program are presented.AMS-02 is a state-of-the-art particle physics detector containing a large superfluid helium-cooled superconducting magnet. Highly sensitive detector plates inside the magnet measure a particle’s speed, mass, charge, and direction. The AMS-02 experiment, which will be flown as an attached payload on the International Space Station, will study the properties and origin of cosmic particles and nuclei including antimatter and dark matter.Two engineering model cryocoolers have been under test at NASA Goddard since November 2001. Qualification testing of the engineering model cryocooler bracket assembly including random vibration and thermal vacuum testing was completed at the end of April 2005. The flight cryocoolers were received in December 2003. Acceptance testing of the flight cryocooler bracket assemblies began in May 2005.     

Instrument for Measuring the Body Mass of Astronauts Under Microgravity Conditions

An improved prototype of the space scale, which has been proposed as a practical and lightweight instrument for measuring the body mass of astronauts under microgravity conditions in the International Space Station (ISS), has been developed. A prominent feature of the proposed instrument is the use of a bungee cord as the source of force. This results in a simple, lightweight, and compact structure of the instrument. It also results in a large displacement during the measurement and then the reduction of the effect of change in subject posture. The feasibility of the prototype design has been evaluated by quantifying the body mass of a human subject in a parabolic flight test. The present and future statuses of the space scale are discussed.     

GEANT4-RIC方法在卫星内放电监测器研制中的应用研究

围绕CRRES卫星内放电监测器在轨试验,国外开展了大量空间内带电的关键性研究,为NASA-HDBK-4002等规范的建立奠定了坚实的基础。针对实验室研制的内放电监测装置,采用GEANT4-RIC数值模拟和地面试验相结合的方法对内放电监测器的放电状况进行了对比研究,验证了模拟方法的正确性,为进一步开展空间辐射效应监测器研制提供了一种新的设计方法 。     

Summary of Recent Research Accomplishment Onboard the International Space Station—Within the United States Orbital Segment

November 20, 2010, marked a significant milestone in the annals of human endeavors in space since it was the twelfth anniversary of one of the most challenging and complex construction projects ever attempted by humans away from our planet: The construction of the International Space Stations. On November 20, 1998, the Zarya Control Module was launched. With this simple, almost unnoticed launch in the science community, the construction of a continuously staffed research platform, in Low Earth Orbit, was underway. This paper discusses the research that was performed by many occupants of this research platform during the year celebrating its twelfth anniversary. The main objectives of this paper are fourfold: (1) to discuss the integrated manner in which science planning/replanning and prioritization during the execution phase of an increment is carried out across the United States Orbital Segment since that segment is made of four independent space agencies; (2) to discuss and summarize the research that was performed during increments 16 and 17 (October 2007 to October 2008). The discussion for these two increments is primarily focused on the main objectives of each investigation and its associated hypotheses that were investigated. Whenever available and approved, preliminary research results are also discussed for each of the investigations performed during these two increments; (3) to compare the planned research portfolio for these two increments versus what was actually accomplished during the execution phase in order to discuss the challenges associated with planning and performing research in a space laboratory located over 240 miles up in space, away from the ground support team; (4) to briefly touch on the research portfolio of increments 18 and 19/20 as the International Space Station begins its next decade in Low Earth Orbit.     

综合集成方法的实践——“中国载人航天发展战略”研究方法总结

中国要不要搞载人航天？怎么搞载人航天？采取何种发展战略和技术途径,涉及政治、经济、军事、社会和科技诸多方面。遵照钱学森院士创建的系统学提出的“定性与定量相结合的综合集成方法”,结合中国国情,以软科学命题,从指导思想、研究步骤和研究方法几方面进行了研究,研究结果表明,“面对世界载人航天的挑战和机遇,中国载人航天不可不搞,也不能大搞,飞船起步,平稳发展万无一失。盲自赶超或急于缩小差距均将陷入困境,疑虑过多以至坐视不顾,也会失掉机会和希望。”文章对该软科学命题做了总结。     

Photosystem II stress tolerance in the unicellular green algaChlamydomonas Reinhardtii under space conditions

Photosynthesis was established on the earth 3.5 billion years ago. Due to the absence of the ozone layer in the early atmosphere it was most likely adapted to the presence of ionizing radiation continuously emitted by solar and stellar flares. That complex radiation spectrum comprises protons, alpha particles, heavy charged particle-HZE, electrons, X-ray and neutrons. Such spectrum has a significant impact on biological systems which capture light energy for e.g. photosynthesis. Oxygenic photosynthesis of plants, algae and cyanobacteria initiates at the level of photosystem II (PSII), a multisubunit protein complex embedded in the thylakoid membrane inside chloroplasts. PSII uses sunlight to power the unique photo-induced oxidation of water to atmospheric oxygen which is indispensable for most life forms. It is an especially sensitive component if exposed to space radiation and thus an important target for research aimed at improving bioregenerative life-support systems. The unicellular green algae Chlamydomonas reinhardtii is a long standing model organism for photosynthesis research. It was exposed to ionizing radiation in the ESA facility Biopan located in the Foton capsule brought to space by the Russian Soyuzfor 15 days. The algae were tested in space under shielded conditions in the past, but they were never exposed to direct ionizing radiation such as in Biopan. Conditions for survival were identified. It was observed that the effect of space stress on the survival of the algae varied depending on the light conditions to which they were exposed during the flight. In some cases the flight experience caused a stimulation of the photosystem II oxygen evolution of the cells.     

Life sciences issues affecting space exploration

The U.S. space program is undertaking a serious examination of new initiatives in human space exploration involving permanent colonies on the Moon and an outpost on Mars. Life scientists have major responsibilities to the crew, to assure their health, productivity, and safety throughout the mission and the postflight rehabilitation period; to the mission, to provide a productive working environment; and to the scientific community, to advance knowledge and understanding of human adaptation to the space environment. Critical areas essential to the support of human exploration include protection from the radiation hazards of the space environment, reduced gravity countermeasures, artificial gravity, medical care, life support systems, and behavior, performance, and human factors in an extraterrestrial environment. Developing solutions to these concerns is at the heart of the NASA Life Sciences ground-based and flight research programs. Facilities analogous to planetary outposts are being considered in Antarctica and other remote settings. Closed ecological life support systems will be tested on Earth and Space Station. For short-duration simulations and tests, the Space Shuttle and Spacelab will be used. Space Station Freedom will provide the essential scientific and technological research in areas that require long exposures to reduced gravity conditions. In preparation for Mars missions, research on the Moon will be vital. As the challenges of sustaining humans on space are resolved, advances in fundamental science, medicine and technology will follow.