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1.
The experiment proposed by Prof. Ricci University of Milan is funded by ASI with Laben as industrial Prime Contractor. ACS-EH (Automated Culture System-Experiment Hardware) will support the multigenerational experiment on weightlessness with rotifers and nematodes within four Experiment Containers (ECs) located inside the European Modular Cultivation System (EMCS) facility..Actually the Phase B is in progress and a concept design solution has been defined. The most challenging aspects for the design of such hardware are, from biological point of view the provision of an environment which permits animal's survival and to maintain desiccated generations separated and from the technical point of view, the miniaturisation of the hardware itself due to the reduce EC provided volume (160mmx60mmx60mm). The miniaturisation will allow a better use of the available EMCS Facility resources (e.g. volume. power etc.) and to fulfil the experiment requirements. ACS-EH, will be ready to fly in the year 2005 on boar the ISS.  相似文献   

2.
MDS (Mice Drawer System) is the Facility that will support the research on board the International Space Station (ISS). Funded by ASI with Laben as industrial Prime Contractor, MDS will also permit its utilisation for other research programs with mice. The most attractive feature of MDS is that six mice can he kept separate inside dedicated and isolated cages. This permits to perform six experiments in parallel, one for each mouse. In the first utilisation flight of MDS facility the selected experiment is devoted to study human bone formation and specific countermeasures to prevent osteoporosis using mice under microgravity conditions as a model.  相似文献   

3.
Columbus, the European Space Agency (ESA) orbital facility laboratory will be launched in December 2007 and attached to the International Space Station (ISS). In its launch configuration, Columbus includes 4 multi-user facilities: one of them is the European Physiology Modules Facility, also called EPM. The EPM will be devoted to Human Physiology; it will be collocated in the Columbus module with two other physiology racks, i.e. the HRF-1 and HRF-2 American racks (Human Research Facility). CADMOS is part of the French Space Agency, located in Toulouse; it has been designated by the European Space Agency as the Facility Responsible Centre (FRC) for the EPM. As a User Support and Operations Centre, CADMOS main tasks are to help the scientists to prepare and perform their experiments in Space and to monitor operations on the ISS.  相似文献   

4.
Following an European Space Agency announcement of opportunity in 1996 for ”Externally mounted payloads for 1st utilization phase” on the International Space Station (ISS), scientists working in the fields of astrobiology proposed experiments aiming at long-term exposure of a variety of chemical compounds and extremely resistant microorganisms to the hostile space environment. The ESA exposure facility EXPOSE was built and an operations´ concept was prepared. The EXPOSE experiments were developed through an intensive pre-flight experiment verification test program. 12 years later, two sets of astrobiological experiments in two EXPOSE facilities have been successfully launched to the ISS for external exposure for up to 1.5 years. EXPOSE-E, now installed at the balcony of the European Columbus module, was launched in February 2008, while EXPOSE-R took off to the ISS in November 2008 and was installed on the external URM-D platform of the Russian Zvezda module in March 2009.  相似文献   

5.
Space experiments provide a unique opportunity to advance our knowledge of how plants respond to the space environment, and specifically to the absence of gravity. The European Modular Cultivation System (EMCS) has been designed as a dedicated facility to improve and standardise plant growth in the International Space Station (ISS). The EMCS is equipped with two centrifuges to perform experiments in microgravity and with variable gravity levels up to 2.0 g. Seven experiments have been performed since the EMCS was operational on the ISS. The objectives of these experiments aimed to elucidate phototropic responses (experiments TROPI‐1 and ‐2), root gravitropic sensing (GRAVI‐1), circumnutation (MULTIGEN‐1), cell wall dynamics and gravity resistance (Cell wall/Resist wall), proteomic identification of signalling players (GENARA‐A) and mechanism of InsP3 signalling (Plant signalling). The role of light in cell proliferation and plant development in the absence of gravity is being analysed in an on‐going experiment (Seedling growth). Based on the lessons learned from the acquired experience, three preselected ISS experiments have been merged and implemented as a single project (Plant development) to study early phases of seedling development. A Topical Team initiated by European Space Agency (ESA), involving experienced scientists on Arabidopsis space research experiments, aims at establishing a coordinated, long‐term scientific strategy to understand the role of gravity in Arabidopsis growth and development using already existing or planned new hardware.  相似文献   

6.
The human serum paraoxonase/arylesterase polymorphism.   总被引:29,自引:2,他引:27       下载免费PDF全文
The heterozygous human serum paraoxonase phenotype can be clearly distinguished from both homozygous phenotypes on the basis of its distinctive ratio of paraoxonase to arylesterase activities. A trimodal distribution of the ratio values was found with 348 individual serum samples, measuring the ratio of paraoxonase activity (with 1 M NaCl in the assay) to arylesterase activity, using phenylacetate. The three modes corresponded to the three paraoxonase phenotypes, A, AB, and B (individual genotypes), and the expected Mendelian segregation of the trait was observed within families. The paraoxonase/arylesterase activity ratio showed codominant inheritance. We have defined the genetic locus determining the aromatic esterase (arylesterase) responsible for the polymorphic paraoxonase activity as esterase-A (ESA) and have designated the two common alleles at this locus by the symbols ESA*A and ESA*B. The frequency of the ESA*A allele was estimated to be .685, and that of the ESA*B allele, 0.315, in a sample population of unrelated Caucasians from the United States. We postulate that a single serum enzyme, with both paraoxonase and arylesterase activity, exists in two different isozymic forms with qualitatively different properties, and that paraoxon is a "discriminating" substrate (having a polymorphic distribution of activity) and phenylacetate is a "nondiscriminating" substrate for the two isozymes. Biochemical evidence for this interpretation includes the cosegregation of the degree of stimulation of paraoxonase activity by salt and paraoxonase/arylesterase activity ratio characteristics; the very high correlation between both the basal (non-salt stimulated) and salt-stimulated paraoxonase activities with arylesterase activity; and the finding that phenylacetate is an inhibitor for paraoxonase activities in both A and B types of enzyme.  相似文献   

7.
Current environmental assessments for petroleum hydrocarbon (PHC) contaminated sites are dependent on discrete soil sampling to estimate the degree and extent of contamination, leading to unreliable and non-reproducible results. Incremental sampling methodology (ISM) involves collecting and combining samples within a targeted area and holds promise for being a cost-effective, representative, and reproducible sampling strategy for contaminated site characterization. We hypothesized that traditional Phase II Environmental Site Assessments (ESA) discrete and ISM sampling protocols were not mutually exclusive, and the two approaches can be used to formulate a responsible land management strategy. Results gathered through ISM were compared to those from Phase II ESA for two PHC contaminated sites in Canada. Both methods indicated the sites were impacted with PHC beyond Saskatchewan Tier I guidance, however, the delineation of the PHC plume differed by as much as 75% for the heavier hydrocarbons. The Phase II ESA methods had higher incidences of false positive results and an overestimation of contamination at depth. A laboratory experiment confirmed that ISM does not “dilute” the samples as to cause underestimation, whereby the hydrocarbon concentrations for a single combined sample was equivalent to the mean of 30 discrete samples. Based on our results, sites should undergo risk assessment based on the estimates of the Phase II ESA results using vapor phase logs to estimate contaminant extent. If exposure pathways cannot be eliminated through the risk assessment process, remediation planning based on the ISM results is justified given the demonstrated cost-effectiveness, representativeness, and reproducibility.  相似文献   

8.
Under separate contracts with ESA (FUMO and ERM Study) and as a link in the development of the European Modular Cultivation System's (EMCS) functionality and biocompatibility, plant studies have been performed at The Plant Biocentre in Trondheim, Norway. The main goal was to test whether the breadboards containing the major components planned for use in the EMCS would be optimal for space experiments with plant material. The test plans and the experimental set-up for the verification of biocompatibility and biological functionality included the use of a few model plant species including cress (Lepidium sativum L.) and Arabidopsis thaliana. The plants were tested at different developmental levels of morphological and physiological complexity (illumination, life support, humidity control, water supply, observation, short- and long-term plant growth experiments and contamination prevention). Results from the tests show that the EMCS concept is useful for long duration plant growth on the ISS.  相似文献   

9.
The European Modular Cultivation System (EMCS) is one of a wide range of laboratory modules under construction by ESA that will be placed on the International Space Station (ISS). In the present study the development and construction of an important component in the EMCS, the Plant Cultivation Container (PCC), is described. The PCC as a "flower pot" will automatically provide the plants with water and liquid nutrients as needed. The PCC is located inside the plant growth unit, the Experiment Container (EC), on the EMCS and interfaces with the EMCS. The essential parts of the PCC are a Peltier element, a micro valve, a monitoring RH sensor with an integrated platinum RTD temperature sensor, a RH sensor that detects air leaving the PCC and controls the peristaltic pump, a DC-DC board that provides correct current to the Peltier element, and a switch/connector board. The PCC is presently being tested out at ESTEC/ESA.  相似文献   

10.
Since February 2002 Kayser-Threde GmbH, Munich (Germany) leads a study under ESA contract in order to study the technical feasibility and the applications of "Scanning Probe Microscopy for Bio & Nanotechnology onboard the ISS (SONOS)". The objective of this effort is to demonstrate the feasibility of an SPM instrument on the ISS. An appropriate breadboard model will be manufactured and tested within the present study. Its development will be based upon the developed pocket size SPM instrument by Professor W. Hecki of the Center for Crystallography and NanoScience (CeNS) at the Ludwig-Maximilians University (LMU) in Munich. Scanning probe microscopy (SPM) investigates surface structures at very high resolution and can perform nanoengineering. These techniques can be applied to non organic as well as to organic or biological materials.  相似文献   

11.
In this paper, we present the results of four pollen diagrams obtained from the northeastern coast of the Iberian Peninsula. These data, together with a set of 11 radiocarbon dates, allow us to make some suggestions about human activity in this area mainly during the last 6000 years. We have established four main stages of this activity. Phase I (7000–3000 B.P.) shows some sporadic human clearance without qualitative and/or quantitative changes inside the natural woodland, except for slight oscillations in AP values. These clearances are synchronous with Neolithic and Bronze Age settlements. Phase II (3000–1500/1300 B.P.) demonstrates a different human action on the landscape along the Catalan coast. Sampling sites located in rich agricultural plains and close to urban centres show continuous woodland clearance during the Iberian period and especially during Roman times. In contrast, at boring sites far from these towns, the irregular and sporadic woodland disturbances continue, although these become more common. Phase III (1500/1300–850 B.P.) shows further woodland clearance fires along the coast. Pollen, archaeological and historical evidence allow us to relate this to the introduction of grazing in the coastal area, connected with seasonal transhumance between the littoral and mountain regions. Phase IV (850–300/150 B.P.) is characterised by the final clearance of woodland and the development of olive farming. During this phase the agrarian Mediterranean landscape was definitively formed.  相似文献   

12.
13.
The immunostimulatory effects of bacterial DNA on mammalian cells have been localized to unmethylated CpG motifs, and synthetic CpG-containing oligodeoxynucleotides that mimic these effects are known as immunostimulatory sequences (ISS). We have found that the polycationic antibiotic, polymyxin B (PMXB), associates with ISS and serum albumin in vitro and forms microparticles that greatly increase the activity of ISS on plasmacytoid dendritic cells (PDCs). Specifically, ISS/PMXB greatly enhanced IFN-alpha production from PDCs and other activities downstream of IFN-alpha, including IFN-gamma secretion, NK lytic activity, and the expression of genes dependent upon IFN-alpha/IFN-gamma. This amplification was specific for the IFN-alpha pathway since other ISS activities, including B cell proliferation, B cell IL-6 secretion, and PDC maturation, were not affected by PMXB. Both the polycationic peptide and lipophilic fatty acid side chain domains of PMXB, as well as the presence of a third party stabilizing agent such as albumin or Tween 85, were required for particle formation and enhanced ISS activity. The ISS-enhancing activity of PMXB was observed across multiple species (human, primate, and mouse) and in vivo (primate, mouse). These data illustrate the usefulness of formulating ISS with a cationic lipopeptide such as PMXB, which focuses and greatly amplifies the ISS-induced pathway of IFN-alpha-mediated responses.  相似文献   

14.
History of the International Space Station, ISS, and planning of its scientific use are described in this essay. Fundamental gravitational biology and its facility on the ISS have been identified to have the highest priority to conduct scientific experiments with variable G environment in orbit. The road map of space activities is clearly directing the efforts toward manned Mars exploration. The Centrifuge is a core element of the facilities dedicated to this endeavor. Several research subjects are discussed with the results obtained from the past space experiments. Direct effects of gravity on the biological system at the level of integrative organisms are major subjects of study that will be conducted on the large scaled centrifuge.  相似文献   

15.
Immunostimulatory sequence (ISS) DNA containing unmethylated CpG dinucleotides stimulate NK and APC to secrete proinflammatory cytokines, including IFN-alphabeta and -gamma, TNF-alpha, and IL-6 and -12, and to express costimulatory surface molecules such as CD40, B7-1, and B7-2. Although ISS DNA has little direct effect on T cells by these criteria, immunization of wild-type mice with ISS DNA and OVA results in Ag-specific CTL and Th1-type T helper activity. This investigation examines the mechanisms by which ISS DNA primes CD8(+) and CD4(+) lymphocyte activities. In this report we demonstrate that ISS DNA regulates the expression of costimulatory molecules and TAP via a novel autocrine or paracrine IFN-alphabeta pathway. Coordinated regulation of B7 costimulation and TAP-dependent cross-presentation results in priming of Ag-specific CD8(+) CTL, whereas CD40, B7, and IL-12 costimulation is required for priming of CD4(+) Th cells by ISS-based vaccines.  相似文献   

16.
BACKGROUND: The aim of this retrospective analysis was to evaluate the effects of growth hormone (GH) treatment on testicular development in boys with idiopathic short stature (ISS) and isolated GH deficiency (IGHD) followed in the KIGS (Pharmacia International Growth Database). METHODS: For inclusion in the study, the patients had to have received more than 1 year of prepubertal GH treatment, at least 4 consecutive years of GH treatment in total, and to have attained their final height, defined as a height velocity of less than 2 cm/year. Data on 107 boys in the KIGS database have been analyzed. RESULTS: No significant differences in duration of GH treatment and testicular volume at the start of treatment or at final height were found between the boys with ISS and those with IGHD. The progression of testicular volume in boys with ISS or IGHD during GH treatment did not differ from the reference population. CONCLUSIONS: This analysis shows that GH treatment does not alter testicular growth in boys with ISS or IGHD. However, prospective controlled studies are needed to rule out moderate attenuating or stimulating effects.  相似文献   

17.
18.
Microbially induced sedimentary structures (MISS) are an important facet of recent paleoichnological work because of their taphonomic implications. MISS are extensively studied in terms of their formation processes, recognition in the ancient record, and their diverse morphologies. Classification and terminology schemes are based on their appearance and mode of formation; however, the taxonomic treatment of MISS remains debated. Traditionally MISS have been considered sedimentary structures, and arguments have been made that they cannot be treated as trace fossils under the International Code of Zoological Nomenclature (ICZN) due to MISS being formed by communities of microbiota including algae, cyanobacteria, and others, rather than a single tracemaker. Here, we reexamine MISS using an ichnotaxonomic approach and apply ichnologic terminology and binomial names. Upon reexamining the holotype of Kinneyia Walcott, a genus commonly used to describe some MISS, we argue it cannot be used to correctly describe wrinkle or ripple-like features seen in MISS, and we agree with previous authors that Kinneyia is likely not biogenic in origin. We here assign a new ichnogenus and ichnospecies, Rugalichnus matthewii, to ripple-like sedimentary wrinkle marks known as MISS, separating them from the nomen dubium genus Kinneyia.  相似文献   

19.
The search for traces of past and present life is a complex and multidisciplinary research activity involving several scientific heritages and a specific industrial ability for planetary exploration. Laben was established in 1958 to design and manufacture electronic instruments for research in nuclear physics. In the mid 2004 the company was merged with Alenia Spazio. It is now part of Alcatel Alenia Space, a French Italian joint venture. Alcatel Alenia Space Italia SpA is a Finmeccanica Company. Currently the plant of Vimodrone provides a wide heritage in life science oriented to space application. The experience in Space Life Science is consolidated in the following research areas: (1) Physiology: Mouse models related to studies on human physiology Human neuroscience research and dosimetry (2) Animal Adaptation and Behaviour: mice behaviour related to stabling stress (3) Developmental Biology: aquatic microorganisms cultivation (4) Cell culture & Biotechnology: Protein crystal growth General purpose Multiwell Next Biotechnology studies and development: Bio reactor, mainly oriented to tissue engineering Microsensor for tissue control (organ replacement) Multiwell for adherent cell culture or for automated biosensor based on cell culture Experiment Container for organic systems Experiment Container for small animals Instrumentation based on fluorescent Biosensors Sensors for Life science experiments for Biopan capsule and Space Vehicle Ray Shielding Materials Random Positioning Machine specialisation (Support ground equipment) The biological features of this heritage is at disposal for the exobiology multi science. The involvement of industries, from the beginning of the exobiology projects, allows a cost effective technologies closed loop development between Research Centres, Principal Investigators and industry.  相似文献   

20.
The thermal stability and kinetic properties of purified NADP+-malate dehydrogenase (NADP+-MDH; EC 1.1.1.82) isomorphs were analyzed from plants of two populations of Barnyard grass from contrasting thermal environments. Plants from Québec (QUE) and Mississippi (MISS) were acclimated under controlled conditions at 26/20°C and 14/8°C (day/night). While the enzyme from QUE showed one isomorph, 3 isomorphs were detected in all plants from MISS, suggesting the presence of gene duplication and fixed heterozygosity for the expression of this dimeric enzyme. This findig raises the possibility that the enhanced acclimatory potential of NADP+-MDH from MISS plants, as found from previous studies with the partially purified and unfractioned enzyme, may result from differential kinetic properties of isomorphs which would allow for the proper modulation of catalysis over a wide temperature range. The thermal stability of the QUE isomorph was significantly higher than that of any of the MISS isomorphs. The apparent activation energy of the QUE isomorph was within the range of values found for the 3 MISS isomorphs which were similar to each other. The Michaelis-Menten constants (Km) for oxalacetic acid were not significantly different among isomorphs or between thermoperiods, but Km (NADP+) values for the QUE isomorph were significantly higher than those of two of the MISS isomorphs over the 15–25°C assay range Vmax/Km ratios for OAA and NADP+ were not significantly different among isomorphs or between thermoperiods. Our data indicate that, under highly purified conditions, the single NADP+-MDH isomorph of QUE plants possesses good acclimatory potential for maintaining catalytic efficiency under a wide range of temperature conditions. In vitro thermal and kinetic data do not support the hypothesis that the the multiple NADP+-MDH isomorphs found in MISS plants may have been selected to optimize the thermal and catalytic efficiency of NADP+-MDH under warm temperature conditions.  相似文献   

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