| 1. |
- Coustenis, A., et al.
(author)
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TandEM : Titan and Enceladus mission
- 2009
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In: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 23:3, s. 893-946
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Journal article (peer-reviewed)abstract
- TandEM was proposed as an L-class (large) mission in response to ESA's Cosmic Vision 2015-2025 Call, and accepted for further studies, with the goal of exploring Titan and Enceladus. The mission concept is to perform in situ investigations of two worlds tied together by location and properties, whose remarkable natures have been partly revealed by the ongoing Cassini-Huygens mission. These bodies still hold mysteries requiring a complete exploration using a variety of vehicles and instruments. TandEM is an ambitious mission because its targets are two of the most exciting and challenging bodies in the Solar System. It is designed to build on but exceed the scientific and technological accomplishments of the Cassini-Huygens mission, exploring Titan and Enceladus in ways that are not currently possible (full close-up and in situ coverage over long periods of time). In the current mission architecture, TandEM proposes to deliver two medium-sized spacecraft to the Saturnian system. One spacecraft would be an orbiter with a large host of instruments which would perform several Enceladus flybys and deliver penetrators to its surface before going into a dedicated orbit around Titan alone, while the other spacecraft would carry the Titan in situ investigation components, i.e. a hot-air balloon (MontgolfiSre) and possibly several landing probes to be delivered through the atmosphere.
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| 2. |
- Fridlund, M., et al.
(author)
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The Search for Worlds Like Our Own
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 5-17
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Journal article (peer-reviewed)abstract
- The direct detection of Earth-like exoplanets orbiting nearby stars and the characterization of such planets particularly, their evolution, their atmospheres, and their ability to host life-constitute a significant problem. The quest for other worlds as abodes of life has been one of mankind's great questions for several millennia. For instance, as stated by Epicurus similar to 300 BC: "Other worlds, with plants and other living things, some of them similar and some of them different from ours, must exist.'' Demokritos from Abdera (460-370 BC), the man who invented the concept of indivisible small parts-atoms-also held the belief that other worlds exist around the stars and that some of these worlds may be inhabited by life-forms. The idea of the plurality of worlds and of life on them has since been held by scientists like Johannes Kepler and William Herschel, among many others. Here, one must also mention Giordano Bruno. Born in 1548, Bruno studied in France and came into contact with the teachings of Nicolas Copernicus. He wrote the book De l'Infinito, Universo e Mondi in 1584, in which he claimed that the Universe was infinite, that it contained an infinite amount of worlds like Earth, and that these worlds were inhabited by intelligent beings. At the time, this was extremely controversial, and eventually Bruno was arrested by the church and burned at the stake in Rome in 1600, as a heretic, for promoting this and other equally confrontational issues (though it is unclear exactly which idea was the one that ultimately brought him to his end). In all the aforementioned cases, the opinions and results were arrived at through reasoning-not by experiment. We have only recently acquired the technological capability to observe planets orbiting stars other than our Sun; acquisition of this capability has been a remarkable feat of our time. We show in this introduction to the Habitability Primer that mankind is at the dawning of an age when, by way of the scientific method and 21(st)-century technology, we will be able to answer this fascinating controversial issue that has persisted for at least 2500 years.
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| 3. |
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| 4. |
- Andersen, M. R., et al.
(author)
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Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88
- 2011
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In: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051 .- 1549-5469. ; 21:6, s. 885-897
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Journal article (peer-reviewed)abstract
- The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compel additional exploration. We therefore undertook wholegenome sequencing of the acidogenic A. niger wild-type strain (ATCC 1015) and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence, and half the telomeric regions have been elucidated. Moreover, sequence information from ATCC 1015 was used to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 Mb of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis supported up-regulation of genes associated with biosynthesis of amino acids that are abundant in glucoamylase A, tRNA-synthases, and protein transporters in the protein producing CBS 513.88 strain. Our results and data sets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi
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| 5. |
- De Schryver, FC, et al.
(author)
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Luminescence spectroscopy and microdomains
- 1994
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In: MICROCHEMISTRY: Spectroscopy and Chemistry in Small Domains; Masuhara H., De Schryver F.C., Kitamura N., Tamai N. (eds), Elsevier, Amsterdam, New York, Tokyo (1994), 415-430.
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Book chapter (peer-reviewed)
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| 6. |
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| 7. |
- Lammer, H., et al.
(author)
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Geophysical and Atmospheric Evolution of Habitable Planets
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 45-68
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Journal article (peer-reviewed)abstract
- The evolution of Earth-like habitable planets is a complex process that depends on the geodynamical and geophysical environments. In particular, it is necessary that plate tectonics remain active over billions of years. These geophysically active environments are strongly coupled to a planet's host star parameters, such as mass, luminosity and activity, orbit location of the habitable zone, and the planet's initial water inventory. Depending on the host star's radiation and particle flux evolution, the composition in the thermosphere, and the availability of an active magnetic dynamo, the atmospheres of Earth-like planets within their habitable zones are differently affected due to thermal and nonthermal escape processes. For some planets, strong atmospheric escape could even effect the stability of the atmosphere.
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| 8. |
- Alibert, Y., et al.
(author)
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Origin and Formation of Planetary Systems
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 19-32
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Journal article (peer-reviewed)abstract
- To estimate the occurrence of terrestrial exoplanets and maximize the chance of finding them, it is crucial to understand the formation of planetary systems in general and that of terrestrial planets in particular. We show that a reliable formation theory should not only explain the formation of the Solar System, with small terrestrial planets within a few AU and gas giants farther out, but also the newly discovered exoplanetary systems with close-in giant planets. Regarding the presently known exoplanets, we stress that our current knowledge is strongly biased by the sensitivity limits of current detection techniques (mainly the radial velocity method). With time and improved detection methods, the diversity of planets and orbits in exoplanetary systems will definitely increase and help to constrain the formation theory further. In this work, we review the latest state of planetary formation in relation to the origin and evolution of habitable terrestrial planets.
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| 9. |
- Brack, A., et al.
(author)
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Origin and Evolution of Life on Terrestrial Planets
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 69-76
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Journal article (peer-reviewed)abstract
- The ultimate goal of terrestrial planet-finding missions is not only to discover terrestrial exoplanets inside the habitable zone (HZ) of their host stars but also to address the major question as to whether life may have evolved on a habitable Earth-like exoplanet outside our Solar System. We note that the chemical evolution that finally led to the origin of life on Earth must be studied if we hope to understand the principles of how life might evolve on other terrestrial planets in the Universe. This is not just an anthropocentric point of view: the basic ingredients of terrestrial life, that is, reduced carbon-based molecules and liquid H2O, have very specific properties. We discuss the origin of life from the chemical evolution of its precursors to the earliest life-forms and the biological implications of the stellar radiation and energetic particle environments. Likewise, the study of the biological evolution that has generated the various life-forms on Earth provides clues toward the understanding of the interconnectedness of life with its environment.
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| 10. |
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| 11. |
- Dvorak, R., et al.
(author)
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Dynamical Habitability of Planetary Systems
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 33-43
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Journal article (peer-reviewed)abstract
- The problem of the stability of planetary systems, a question that concerns only multiplanetary systems that host at least two planets, is discussed. The problem of mean motion resonances is addressed prior to discussion of the dynamical structure of the more than 350 known planets. The difference with regard to our own Solar System with eight planets on low eccentricity is evident in that 60% of the known extrasolar planets have orbits with eccentricity e > 0.2. We theoretically highlight the studies concerning possible terrestrial planets in systems with a Jupiter-like planet. We emphasize that an orbit of a particular nature only will keep a planet within the habitable zone around a host star with respect to the semimajor axis and its eccentricity. In addition, some results are given for individual systems (e.g., Gl777A) with regard to the stability of orbits within habitable zones. We also review what is known about the orbits of planets in double-star systems around only one component ( e. g., gamma Cephei) and around both stars (e.g., eclipsing binaries).
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| 12. |
- Fridlund, M., et al.
(author)
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A Roadmap for the Detection and Characterization of Other Earths
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 113-119
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Journal article (peer-reviewed)abstract
- The European Space Agency and other space agencies such as NASA recognize that the question with regard to life beyond Earth in general, and the associated issue of the existence and study of exoplanets in particular, is of paramount importance for the 21(st) century. The new Cosmic Vision science plan, Cosmic Vision 2015-2025, which is built around four major themes, has as its first theme: "What are the conditions for planet formation and the emergence of life?'' This main theme is addressed through further questions: (1) How do gas and dust give rise to stars and planets? (2) How will the search for and study of exoplanets eventually lead to the detection of life outside Earth (biomarkers*)? (3) How did life in the Solar System arise and evolve? Although ESA has busied itself with these issues since the beginning of the Darwin study in 1996, it has become abundantly clear that, as these topics have evolved, only a very large effort, addressed from the ground and from space with the utilization of different instruments and space missions, can provide the empirical results required for a complete understanding. The good news is that the problems can be addressed and solved within a not-too-distant future. In this short essay, we present the present status of a roadmap related to projects that are related to the key long-term goal of understanding and characterizing exoplanets, in particular Earthlike planets.
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| 13. |
- Glauser, A. M., et al.
(author)
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Characterizing exoplanets in the visible and infrared: A spectrometer concept for the EChO space mission
- 2013
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In: Journal of Astronomical Instrumentation. - 2251-1725 .- 2251-1717. ; 2:1
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Journal article (peer-reviewed)abstract
- Transit-spectroscopy of exoplanets is one of the key observational techniques used to characterize extrasolar planets and their atmospheres. The observational challenges of these measurements require dedicated instrumentation and only the space environment allows undisturbed access to earth-like atmospheric features such as water or carbon dioxide. Therefore, several exoplanet-specific space missions are currently being studied. One of them is EChO, the Exoplanet Characterization Observatory, which is part of ESA's Cosmic Vision 2015-2025 program, and which is one of four candidates for the M3 launch slot in 2024. In this paper we present the results of our assessment study of the EChO spectrometer, the only science instrument onboard this spacecraft. The instrument is a multi-channel all-reflective dispersive spectrometer, covering the wavelength range from 400 nm to 16μm simultaneously with a moderately low spectral resolution. We illustrate how the key technical challenge of the EChO mission - the high photometric stability - influences the choice of spectrometer concept and fundamentally drives the instrument design. First performance evaluations underline the suitability of the elaborated design solution for the needs of the EChO mission.
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| 14. |
- Grenfell, J. L., et al.
(author)
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Co-Evolution of Atmospheres, Life, and Climate
- 2010
-
In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 77-88
-
Journal article (peer-reviewed)abstract
- After Earth's origin, our host star, the Sun, was shining 20-25% less brightly than today. Without greenhouse-like conditions to warm the atmosphere, our early planet would have been an ice ball, and life may never have evolved. But life did evolve, which indicates that greenhouse gases must have been present on early Earth to warm the planet. Evidence from the geological record indicates an abundance of the greenhouse gas CO2. CH4 was probably present as well; and, in this regard, methanogenic bacteria, which belong to a diverse group of anaerobic prokaryotes that ferment CO2 plus H-2 to CH4, may have contributed to modification of the early atmosphere. Molecular oxygen was not present, as is indicated by the study of rocks from that era, which contain iron carbonate rather than iron oxide. Multicellular organisms originated as cells within colonies that became increasingly specialized. The development of photosynthesis allowed the Sun's energy to be harvested directly by life-forms. The resultant oxygen accumulated in the atmosphere and formed the ozone layer in the upper atmosphere. Aided by the absorption of harmful UV radiation in the ozone layer, life colonized Earth's surface. Our own planet is a very good example of how life-forms modified the atmosphere over the planets' lifetime. We show that these facts have to be taken into account when we discover and characterize atmospheres of Earth-like exoplanets. If life has originated and evolved on a planet, then it should be expected that a strong co-evolution occurred between life and the atmosphere, the result of which is the planet's climate.
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| 15. |
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| 16. |
- Kaltenegger, L., et al.
(author)
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Deciphering Spectral Fingerprints of Habitable Exoplanets
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 89-102
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Journal article (peer-reviewed)abstract
- We discuss how to read a planet's spectrum to assess its habitability and search for the signatures of a biosphere. After a decade rich in giant exoplanet detections, observation techniques have advanced to a level where we now have the capability to find planets of less than 10 Earth masses (M-Earth) (so-called "super Earths''), which may be habitable. How can we characterize those planets and assess whether they are habitable? This new field of exoplanet search has shown an extraordinary capacity to combine research in astrophysics, chemistry, biology, and geophysics into a new and exciting interdisciplinary approach to understanding our place in the Universe. The results of a first-generation mission will most likely generate an amazing scope of diverse planets that will set planet formation, evolution, and our planet into an overall context.
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| 17. |
- Kaltenegger, L., et al.
(author)
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Stellar Aspects of Habitability-Characterizing Target Stars for Terrestrial Planet-Finding Missions
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 103-112
-
Journal article (peer-reviewed)abstract
- We present and discuss the criteria for selecting potential target stars suitable for the search for Earth-like planets, with a special emphasis on the stellar aspects of habitability. Missions that search for terrestrial exoplanets will explore the presence and habitability of Earth-like exoplanets around several hundred nearby stars, mainly F, G, K, and M stars. The evaluation of the list of potential target systems is essential in order to develop mission concepts for a search for terrestrial exoplanets. Using the Darwin All Sky Star Catalogue (DASSC), we discuss the selection criteria, configuration-dependent subcatalogues, and the implication of stellar activity for habitability.
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| 18. |
- Korede, Vikram, et al.
(author)
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Design and Validation of a Droplet-based Microfluidic System To Study Non-Photochemical Laser-Induced Nucleation of Potassium Chloride Solutions
- 2023
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In: Crystal Growth & Design. - : American Chemical Society (ACS). - 1528-7483 .- 1528-7505. ; 23:8, s. 6067-6080
-
Journal article (peer-reviewed)abstract
- Non-photochemicallaser-induced nucleation (NPLIN) hasemergedas a promising primary nucleation control technique offering spatiotemporalcontrol over crystallization with potential for polymorph control.So far, NPLIN was mostly investigated in milliliter vials, throughlaborious manual counting of the crystallized vials by visual inspection.Microfluidics represents an alternative to acquiring automated andstatistically reliable data. Thus we designed a droplet-based microfluidicplatform capable of identifying the droplets with crystals emergingupon Nd:YAG laser irradiation using the deep learning method. In ourexperiments, we used supersaturated solutions of KCl in water, andthe effect of laser intensity, wavelength (1064, 532, and 355 nm),solution supersaturation (S), solution filtration,and intentional doping with nanoparticles on the nucleation probabilityis quantified and compared to control cooling crystallization experiments.Ability of dielectric polarization and the nanoparticle heating mechanismsproposed for NPLIN to explain the acquired results is tested. Solutionswith lower supersaturation (S = 1.05) exhibit significantlyhigher NPLIN probabilities than those in the control experiments forall laser wavelengths above a threshold intensity (50 MW/cm(2)). At higher supersaturation studied (S = 1.10),irradiation was already effective at lower laser intensities (10 MW/cm(2)). No significant wavelength effect was observed besides irradiationwith 355 nm light at higher laser intensities (& GE;50 MW/cm(2)). Solution filtration and intentional doping experimentsshowed that nanoimpurities might play a significant role in explainingNPLIN phenomena. Thearticle describes a droplet-based microfluidic setupto study NPLIN with the droplets containing crystals identified usingthe deep-learning method. Experimental parameters such as solutionsupersaturation, laser wavelength, laser intensity, solution filtration,and intentional doping of nanoparticles are studied using supersaturatedaqueous KCl solutions to quantify its influence on nucleation kineticsand draw parallels to the proposed underlying NPLIN mechanisms inthe literature.
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| 19. |
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| 20. |
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| 21. |
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| 22. |
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| 23. |
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| 24. |
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| 25. |
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| 26. |
- Nooijen, Carla F., et al.
(author)
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Exercise self-efficacy in persons with spinal cord injury : psychometric properties of the Dutch translation of the Exercise Self-Efficacy Scale
- 2013
-
In: Journal of Rehabilitation Medicine. - : Medical Journals Sweden AB. - 1650-1977 .- 1651-2081. ; 45:4, s. 347-50
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Journal article (peer-reviewed)abstract
- OBJECTIVE: To assess the reliability and validity of the Dutch version of the exercise self-efficacy scale (ESES) in persons with spinal cord injury. This is the first independent study of ESES psychometric properties, and the first report on ESES test-retest reliability. SUBJECTS/PATIENTS: A total of 53 Dutch persons with spinal cord injury. METHODS: Subjects completed the Dutch ESES twice, with 2 weeks between (ESES_1 and ESES_2). Subjects also completed the General self-efficacy scale (GSE), and a questionnaire regarding demographic characteristics and lesion characteristics. Psychometric properties of the Dutch translation of the ESES were assessed and compared with those of the original English-language version. RESULTS: The Dutch ESES was found to have good internal consistency (Cronbach's alpha for ESES_1 = 0.90, ESES_2 = 0.88). Test-retest reliability was adequate (intra-class correlation coefficient = 0.81, 95% confidence interval 0.70-0.89). For validity, a moderate, statistically significant correlation was found between ESES and the GSE (Spearman's rho ESES_1 = 0.52, ESES_2 = 0.66, p < 0.01). Furthermore, the psychometric properties of the Dutch ESES were found to be similar to those of the original English version. CONCLUSION: The results of this study support the use of the ESES as a reliable and valid measure of exercise self-efficacy.
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| 27. |
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| 28. |
- Sandberg Wollheim, Magnhild, et al.
(author)
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Pregnancy outcomes during treatment with interferon beta-1a in patients with multiple sclerosis.
- 2005
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In: Neurology. - : Ovid Technologies (Wolters Kluwer Health). - 1526-632X .- 0028-3878. ; 65:6, s. 802-806
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Journal article (peer-reviewed)abstract
- Background: Although patients with multiple sclerosis (MS) are advised to stop interferon (IFN) beta-1a therapy before becoming pregnant, some patients become pregnant while on treatment. Methods: We examined individual patient data from eight clinical trials with IFN beta-1a. Results: Of 3,361 women in the studies, 69 pregnancies were reported, of which 41 were patients receiving (or who had stopped receiving within 2 weeks prior to conception) IFN beta-1a (in utero exposure group), 22 were patients who discontinued IFN beta-1a treatment more than 2 weeks before conception (previous exposure group), and six were patients receiving placebo. The 41 in utero exposure pregnancies resulted in 20 healthy full-term infants, one healthy premature infant, nine induced abortions, eight spontaneous abortions, one fetal death, and one congenital anomaly (hydrocephalus). One patient was lost to follow-up. The 22 previous exposure pregnancies resulted in 20 full-term healthy infants, one healthy premature infant, and one birth-related congenital anomaly (Erb palsy) Conclusions: The majority (21/31) of pregnancies that had the potential to go to full term produced healthy infants. The rate of spontaneous abortion was higher, but not significantly so, in the in utero exposure group compared to general population estimates. Until more exposure data become available, patients remain advised to stop IFN beta therapy before becoming pregnant.
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| 29. |
- Schneider, J., et al.
(author)
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The Far Future of Exoplanet Direct Characterization
- 2010
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In: Astrobiology. - : Mary Ann Liebert Inc. - 1531-1074 .- 1557-8070. ; 10:1, s. 121-126
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Journal article (peer-reviewed)abstract
- We describe future steps in the direct characterization of habitable exoplanets subsequent to medium and large mission projects currently underway and investigate the benefits of spectroscopic and direct imaging approaches. We show that, after third- and fourth-generation missions have been conducted over the course of the next 100 years, a significant amount of time will lapse before we will have the capability to observe directly the morphology of extrasolar organisms.
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| 30. |
- Tinetti, G., et al.
(author)
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EChO : Exoplanet characterisation observatory
- 2012
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In: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 34:2, s. 311-353
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Journal article (peer-reviewed)abstract
- A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context and by addressing the suitability of planets for the presence of life. EChO-the Exoplanet Characterisation Observatory-is a mission concept specifically geared for this purpose. EChO will provide simultaneous, multi-wavelength spectroscopic observations on a stable platform that will allow very long exposures. The use of passive cooling, few moving parts and well established technology gives a low-risk and potentially long-lived mission. EChO will build on observations by Hubble, Spitzer and ground-based telescopes, which discovered the first molecules and atoms in exoplanetary atmospheres. However, EChO's configuration and specifications are designed to study a number of systems in a consistent manner that will eliminate the ambiguities affecting prior observations. EChO will simultaneously observe a broad enough spectral region-from the visible to the mid-infrared-to constrain from one single spectrum the temperature structure of the atmosphere, the abundances of the major carbon and oxygen bearing species, the expected photochemically-produced species and magnetospheric signatures. The spectral range and resolution are tailored to separate bands belonging to up to 30 molecules and retrieve the composition and temperature structure of planetary atmospheres. The target list for EChO includes planets ranging from Jupiter-sized with equilibrium temperatures Teq up to 2,000 K, to those of a few Earth masses, with Teq \u223c 300 K. The list will include planets with no Solar System analog, such as the recently discovered planets GJ1214b, whose density lies between that of terrestrial and gaseous planets, or the rocky-iron planet 55 Cnc e, with day-side temperature close to 3,000 K. As the number of detected exoplanets is growing rapidly each year, and the mass and radius of those detected steadily decreases, the target list will be constantly adjusted to include the most interesting systems. We have baselined a dispersive spectrograph design covering continuously the 0. 4-16 μm spectral range in 6 channels (1 in the visible, 5 in the InfraRed), which allows the spectral resolution to be adapted from several tens to several hundreds, depending on the target brightness. The instrument will be mounted behind a 1. 5 m class telescope, passively cooled to 50 K, with the instrument structure and optics passively cooled to \u223c45 K. EChO will be placed in a grand halo orbit around L2. This orbit, in combination with an optimised thermal shield design, provides a highly stable thermal environment and a high degree of visibility of the sky to observe repeatedly several tens of targets over the year. Both the baseline and alternative designs have been evaluated and no critical items with Technology Readiness Level (TRL) less than 4-5 have been identified. We have also undertaken a first-order cost and development plan analysis and find that EChO is easily compatible with the ESA M-class mission framework. © 2012 Springer Science+Business Media B.V.
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| 31. |
- van der Heide, E., et al.
(author)
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Wear of aluminium bronze in sliding contact with lubricated stainless steel sheet material
- 2006
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In: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 261:1, s. 68-73
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Journal article (peer-reviewed)abstract
- Aluminium bronze, well known for its good sliding properties, is frequently applied as tool material in sheet metal forming (SMF) of stainless steel, e.g. for the production of washing, refrigeration and cooking equipment. The limited hardness of the material makes it, however, sensitive to tool wear that is: volumetric wear of the tool due to sliding contact with the sheet material. Conventional wear tests like the rubber wheel abrasion test or the Taber abrader test cannot be used to simulate the interaction of the tooling with lubricated sheet material. Dedicated tribo tests are therefore conducted with the slider-on-sheet test. The aim of the research is to measure the specific wear rate of aluminium bronze at SMF-like conditions. Experimental results showed a pronounced influence of lubricant selection and sheet material selection. The measured specific wear rate varied from 10(-8) mm(3)/N m for a smooth stainless steel sheet quality to 10(-6) mm(3)/N m for a rough surface quality.
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| 32. |
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