GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Cambridge University Press (CUP) ; 2009
    In:  Proceedings of the International Astronomical Union Vol. 5, No. H15 ( 2009-11), p. 708-709
    In: Proceedings of the International Astronomical Union, Cambridge University Press (CUP), Vol. 5, No. H15 ( 2009-11), p. 708-709
    Abstract: In this study, we model the internal structure of CoRoT-7b, considered as a typical extrasolar terrestrial planet, using mass and energy balance constraints. Our results suggest that the deep interior is predominantly composed of dry silicate rock, similar to the Earth's Moon. A central iron core, if present, would be relatively small and less massive ( 〈 15 wt.% of the planet's total mass) as compared to the Earth's (core mass fraction 32.6 wt.%). Furthermore, a partly molten near-surface magma ocean could be maintained, provided surface temperatures were high enough and the rock component mainly composed of Earth-like mineral phase assemblages.
    Type of Medium: Online Resource
    ISSN: 1743-9213 , 1743-9221
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2009
    detail.hit.zdb_id: 2170724-8
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    Cambridge University Press (CUP) ; 2012
    In:  Proceedings of the International Astronomical Union Vol. 8, No. S293 ( 2012-08), p. 350-355
    In: Proceedings of the International Astronomical Union, Cambridge University Press (CUP), Vol. 8, No. S293 ( 2012-08), p. 350-355
    Abstract: Mass and radius of planets transiting their host stars are provided by radial velocity and photometric observations. Structural models of solid exoplanet interiors are then constructed by using equations of state for the radial density distribution, which are compliant with the thermodynamics of the high-pressure limit. However, to some extent those structural models suffer from inherent degeneracy or non-uniqueness problems owing to a principal lack of knowledge of the internal differentiation state and/or the possible presence of an optically thick atmosphere. We here discuss the role of corresponding measurement errors, which adversely affect determinations of a planet's mean density and bulk chemical composition. Precise measurements of planet radii will become increasingly important as key observational constraints for radial density models of individual solid low-mass exoplanets or super-Earths.
    Type of Medium: Online Resource
    ISSN: 1743-9213 , 1743-9221
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2012
    detail.hit.zdb_id: 2170724-8
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Advances in Space Research, Elsevier BV, Vol. 42, No. 8 ( 2008-10), p. 1405-1413
    Type of Medium: Online Resource
    ISSN: 0273-1177
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2008
    detail.hit.zdb_id: 2023311-5
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    Cambridge University Press (CUP) ; 2010
    In:  Proceedings of the International Astronomical Union Vol. 6, No. S276 ( 2010-10), p. 193-197
    In: Proceedings of the International Astronomical Union, Cambridge University Press (CUP), Vol. 6, No. S276 ( 2010-10), p. 193-197
    Abstract: The present study takes the CoRoT-7b exoplanet as an analogue for massive terrestrial planets to investigate conditions, under which intrinsic magnetic fields could be sustained in liquid cores. We examine the effect of depth-dependent transport parameters (e.g., activation volume of mantle rock) on a planet's thermal structure and the related heat flux across the core mantle boundary. For terrestrial planets more massive than the Earth, our calculations suggest that a substantial part of the lowermost mantle is in a sluggish convective regime, primarily due to pressure effects on viscosity. Hence, we find substantially higher core temperatures than previously reported from parameterized convection models. We also discuss the effect of melting point depression in the presence of impurities (e.g., sulfur) in iron-rich cores and compare corresponding melting relations to the calculated thermal structure. Since impurity effects become less important at the elevated pressure and temperature conditions prevalent in the deep interior of CoRoT-7b, iron-rich cores are likely solid, implying that a self-sustained magnetic field would be absent.
    Type of Medium: Online Resource
    ISSN: 1743-9213 , 1743-9221
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2010
    detail.hit.zdb_id: 2170724-8
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    In: Space Science Reviews, Springer Science and Business Media LLC, Vol. 216, No. 5 ( 2020-08)
    Abstract: In this chapter, the key technologies and the instrumentation required for the subsurface exploration of ocean worlds are discussed. The focus is laid on Jupiter’s moon Europa and Saturn’s moon Enceladus because they have the highest potential for such missions in the near future. The exploration of their oceans requires landing on the surface, penetrating the thick ice shell with an ice-penetrating probe, and probably diving with an underwater vehicle through dozens of kilometers of water to the ocean floor, to have the chance to find life, if it exists. Technologically, such missions are extremely challenging. The required key technologies include power generation, communications, pressure resistance, radiation hardness, corrosion protection, navigation, miniaturization, autonomy, and sterilization and cleaning. Simpler mission concepts involve impactors and penetrators or – in the case of Enceladus – plume-fly-through missions.
    Type of Medium: Online Resource
    ISSN: 0038-6308 , 1572-9672
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2020
    detail.hit.zdb_id: 2017804-9
    detail.hit.zdb_id: 2561549-X
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: JAMA Ophthalmology, American Medical Association (AMA), Vol. 141, No. 3 ( 2023-03-01), p. 268-
    Abstract: The DRCR Retina Network Protocol AC showed no significant difference in visual acuity outcomes over 2 years between treatment with aflibercept monotherapy and bevacizumab first with switching to aflibercept for suboptimal response in treating diabetic macular edema (DME). Understanding the estimated cost and cost-effectiveness of these approaches is important. Objective To evaluate the cost and cost-effectiveness of aflibercept monotherapy vs bevacizumab-first strategies for DME treatment. Design, Setting, and Participants This economic evaluation was a preplanned secondary analysis of a US randomized clinical trial of participants aged 18 years or older with center-involved DME and best-corrected visual acuity of 20/50 to 20/320 enrolled from December 15, 2017, through November 25, 2019. Interventions Aflibercept monotherapy or bevacizumab first, switching to aflibercept in eyes with protocol-defined suboptimal response. Main Outcomes and Measures Between February and July 2022, the incremental cost-effectiveness ratio (ICER) in cost per quality-adjusted life-year (QALY) over 2 years was assessed. Efficacy and resource utilization data from the randomized clinical trial were used with health utility mapping from the literature and Medicare unit costs. Results This study included 228 participants (median age, 62 [range, 34-91 years; 116 [51%] female and 112 [49%] male; 44 [19%] Black or African American, 60 [26%] Hispanic or Latino, and 117 [51%] White) with 1 study eye. The aflibercept monotherapy group included 116 participants, and the bevacizumab-first group included 112, of whom 62.5% were eventually switched to aflibercept. Over 2 years, the cost of aflibercept monotherapy was $26 504 (95% CI, $24 796-$28 212) vs $13 929 (95% CI, $11 984-$15 874) for the bevacizumab-first group, a difference of $12 575 (95% CI, $9987-$15 163). The aflibercept monotherapy group gained 0.015 (95% CI, −0.011 to 0.041) QALYs using the better-seeing eye and had an ICER of $837 077 per QALY gained compared with the bevacizumab-first group. Aflibercept could be cost-effective with an ICER of $100 000 per QALY if the price per dose were $305 or less or the price of bevacizumab was $1307 per dose or more. Conclusions and Relevance Variability in individual needs will influence clinician and patient decisions about how to treat specific eyes with DME. While the bevacizumab-first group costs still averaged approximately $14 000 over 2 years, this approach, as used in this study, may confer substantial cost savings on a societal level without sacrificing visual acuity gains over 2 years compared with aflibercept monotherapy.
    Type of Medium: Online Resource
    ISSN: 2168-6165
    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Online Resource
    Online Resource
    Elsevier BV ; 2001
    In:  Planetary and Space Science Vol. 49, No. 14-15 ( 2001-12), p. 1561-1570
    In: Planetary and Space Science, Elsevier BV, Vol. 49, No. 14-15 ( 2001-12), p. 1561-1570
    Type of Medium: Online Resource
    ISSN: 0032-0633
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2001
    detail.hit.zdb_id: 2012795-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Astronomy & Astrophysics, EDP Sciences, Vol. 643 ( 2020-11), p. A81-
    Abstract: Context. The magma ocean period was a critical phase determining how Earth’s atmosphere developed into habitability. However, there are major uncertainties in the role of key processes such as outgassing from the planetary interior and escape of species to space that play a major role in determining the atmosphere of early Earth. Aims. We investigate the effect of outgassing of various species and escape of H 2 for different mantle redox states upon the composition and evolution of the atmosphere for the magma ocean period. Methods. We included an important new atmosphere-interior coupling mechanism: the redox evolution of the mantle, which strongly affects the outgassing of species. We simulated the volatile outgassing and chemical speciation at the surface for various redox states of the mantle by employing a C-H-O based chemical speciation model combined with an interior outgassing model. We then applied a line-by-line radiative transfer model to study the remote appearance of the planet in terms of the infrared emission and transmission. Finally, we used a parameterized diffusion-limited and XUV energy-driven atmospheric escape model to calculate the loss of H 2 to space. Results. We have simulated the thermal emission and transmission spectra for reduced and oxidized atmospheres present during the magma ocean period of Earth. Reduced/thin atmospheres consisting of H 2 in abundance emit more radiation to space and have a larger effective height than oxidized/thick atmospheres, which are abundant in H 2 O and CO 2 . We obtain that the outgassing rates of H 2 from the mantle into the atmosphere are a factor of ten times higher than the rates of diffusion-limited escape to space. We estimate the timescale of total mass loss of outgassed H 2 via escape to be few tens of million years, which is comparable to other studies. Conclusions. Our work presents useful insight into the development of the terrestrial atmosphere during the magma ocean period and provides input to guide future studies that discuss exoplanetary interior compositions and their possible links with atmospheric compositions that might be estimated from observed infrared spectra by future missions.
    Type of Medium: Online Resource
    ISSN: 0004-6361 , 1432-0746
    RVK:
    RVK:
    Language: English
    Publisher: EDP Sciences
    Publication Date: 2020
    detail.hit.zdb_id: 1458466-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Sensors, MDPI AG, Vol. 23, No. 13 ( 2023-07-07), p. 6208-
    Abstract: One of the strengths of laser-induced breakdown spectroscopy (LIBS) is that a large amount of data can be measured relatively easily in a short time, which makes LIBS interesting in many areas, from geomaterial analysis with portable handheld instruments to applications for the exploration of planetary surfaces. Statistical methods, therefore, play an important role in analyzing the data to detect not only individual compositions but also trends and correlations. In this study, we apply two approaches to explore the LIBS data of geomaterials measured with a handheld device at different locations on the Aeolian island of Vulcano, Italy. First, we use the established method, principal component analysis (PCA), and second we adopt the principle of the interesting features finder (IFF), which was recently proposed for the analysis of LIBS imaging data. With this method it is possible to identify spectra that contain emission lines of minor and trace elements that often remain undetected with variance-based methods, such as PCA. We could not detect any spectra with IFF that were not detected with PCA when applying both methods to our LIBS field data. The reason for this may be the nature of our field data, which are subject to more experimental changes than data measured in laboratory settings, such as LIBS imaging data, for which the IFF was introduced first. In conclusion, however, we found that the two approaches complement each other well, making the exploration of the data more intuitive, straightforward, and efficient.
    Type of Medium: Online Resource
    ISSN: 1424-8220
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2052857-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    In: Experimental Astronomy, Springer Science and Business Media LLC, Vol. 33, No. 2-3 ( 2012-4), p. 753-791
    Type of Medium: Online Resource
    ISSN: 0922-6435 , 1572-9508
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2012
    detail.hit.zdb_id: 2012330-9
    SSG: 16,12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...