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  • Pantazis, N, et al. (author)
  • Determining the likely place of HIV acquisition for migrants in Europe combining subject-specific information and biomarkers data
  • 2019
  • In: Statistical methods in medical research. - : SAGE Publications. - 1477-0334 .- 0962-2802. ; 28:7, s. 1979-1997
  • Journal article (peer-reviewed)abstract
    • In most HIV-positive individuals, infection time is only known to lie between the time an individual started being at risk for HIV and diagnosis time. However, a more accurate estimate of infection time is very important in certain cases. For example, one of the objectives of the Advancing Migrant Access to Health Services in Europe (aMASE) study was to determine if HIV-positive migrants, diagnosed in Europe, were infected pre- or post-migration. We propose a method to derive subject-specific estimates of unknown infection times using information from HIV biomarkers’ measurements, demographic, clinical, and behavioral data. We assume that CD4 cell count (CD4) and HIV-RNA viral load trends after HIV infection follow a bivariate linear mixed model. Using post-diagnosis CD4 and viral load measurements and applying the Bayes’ rule, we derived the posterior distribution of the HIV infection time, whereas the prior distribution was informed by AIDS status at diagnosis and behavioral data. Parameters of the CD4–viral load and time-to-AIDS models were estimated using data from a large study of individuals with known HIV infection times (CASCADE). Simulations showed substantial predictive ability (e.g. 84% of the infections were correctly classified as pre- or post-migration). Application to the aMASE study ( n = 2009) showed that 47% of African migrants and 67% to 72% of migrants from other regions were most likely infected post-migration. Applying a Bayesian method based on bivariate modeling of CD4 and viral load, and subject-specific information, we found that the majority of HIV-positive migrants in aMASE were most likely infected after their migration to Europe.
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  • Shepherd, L., et al. (author)
  • Infection-related and -unrelated malignancies, HIV and the aging population
  • 2016
  • In: HIV Medicine. - : Wiley. - 1464-2662 .- 1468-1293. ; 17:8, s. 590-600
  • Journal article (peer-reviewed)abstract
    • Objectives: HIV-positive people have increased risk of infection-related malignancies (IRMs) and infection-unrelated malignancies (IURMs). The aim of the study was to determine the impact of aging on future IRM and IURM incidence. Methods: People enrolled in EuroSIDA and followed from the latest of the first visit or 1 January 2001 until the last visit or death were included in the study. Poisson regression was used to investigate the impact of aging on the incidence of IRMs and IURMs, adjusting for demographic, clinical and laboratory confounders. Linear exponential smoothing models forecasted future incidence. Results: A total of 15 648 people contributed 95 033 person-years of follow-up, of whom 610 developed 643 malignancies [IRMs: 388 (60%); IURMs: 255 (40%)]. After adjustment, a higher IRM incidence was associated with a lower CD4 count [adjusted incidence rate ratio (aIRR) CD4 count < 200 cells/μL: 3.77; 95% confidence interval (CI) 2.59, 5.51; compared with ≥ 500 cells/μL], independent of age, while a CD4 count < 200 cells/μL was associated with IURMs in people aged < 50 years only (aIRR: 2.51; 95% CI 1.40–4.54). Smoking was associated with IURMs (aIRR: 1.75; 95% CI 1.23, 2.49) compared with never smokers in people aged ≥ 50 years only, and not with IRMs. The incidences of both IURMs and IRMs increased with older age. It was projected that the incidence of IRMs would decrease by 29% over a 5-year period from 3.1 (95% CI 1.5–5.9) per 1000 person-years in 2011, whereas the IURM incidence would increase by 44% from 4.1 (95% CI 2.2–7.2) per 1000 person-years over the same period. Conclusions: Demographic and HIV-related risk factors for IURMs (aging and smoking) and IRMs (immunodeficiency and ongoing viral replication) differ markedly and the contribution from IURMs relative to IRMs will continue to increase as a result of aging of the HIV-infected population, high smoking and lung cancer prevalence and a low prevalence of untreated HIV infection. These findings suggest the need for targeted preventive measures and evaluation of the cost−benefit of screening for IURMs in HIV-infected populations.
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  • Chown, Ryan, et al. (author)
  • PDRs4All: IV. An embarrassment of riches: Aromatic infrared bands in the Orion Bar
  • 2024
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 685
  • Journal article (peer-reviewed)abstract
    • Context. Mid-infrared observations of photodissociation regions (PDRs) are dominated by strong emission features called aromatic infrared bands (AIBs). The most prominent AIBs are found at 3.3, 6.2, 7.7, 8.6, and 11.2 µm. The most sensitive, highest-resolution infrared spectral imaging data ever taken of the prototypical PDR, the Orion Bar, have been captured by JWST. These high-quality data allow for an unprecedentedly detailed view of AIBs. Aims. We provide an inventory of the AIBs found in the Orion Bar, along with mid-IR template spectra from five distinct regions in the Bar: the molecular PDR (i.e. the three H2 dissociation fronts), the atomic PDR, and the H II region. Methods. We used JWST NIRSpec IFU and MIRI MRS observations of the Orion Bar from the JWST Early Release Science Program, PDRs4All (ID: 1288). We extracted five template spectra to represent the morphology and environment of the Orion Bar PDR. We investigated and characterised the AIBs in these template spectra. We describe the variations among them here. Results. The superb sensitivity and the spectral and spatial resolution of these JWST observations reveal many details of the AIB emission and enable an improved characterization of their detailed profile shapes and sub-components. The Orion Bar spectra are dominated by the well-known AIBs at 3.3, 6.2, 7.7, 8.6, 11.2, and 12.7 µm with well-defined profiles. In addition, the spectra display a wealth of weaker features and sub-components. The widths of many AIBs show clear and systematic variations, being narrowest in the atomic PDR template, but showing a clear broadening in the H II region template while the broadest bands are found in the three dissociation front templates. In addition, the relative strengths of AIB (sub-)components vary among the template spectra as well. All AIB profiles are characteristic of class A sources as designated by Peeters (2022, A&A, 390, 1089), except for the 11.2 µm AIB profile deep in the molecular zone, which belongs to class B11.2. Furthermore, the observations show that the sub-components that contribute to the 5.75, 7.7, and 11.2 µm AIBs become much weaker in the PDR surface layers. We attribute this to the presence of small, more labile carriers in the deeper PDR layers that are photolysed away in the harsh radiation field near the surface. The 3.3/11.2 AIB intensity ratio decreases by about 40% between the dissociation fronts and the H II region, indicating a shift in the polycyclic aromatic hydrocarbon (PAH) size distribution to larger PAHs in the PDR surface layers, also likely due to the effects of photochemistry. The observed broadening of the bands in the molecular PDR is consistent with an enhanced importance of smaller PAHs since smaller PAHs attain a higher internal excitation energy at a fixed photon energy. Conclusions. Spectral-imaging observations of the Orion Bar using JWST yield key insights into the photochemical evolution of PAHs, such as the evolution responsible for the shift of 11.2 µm AIB emission from class B11.2 in the molecular PDR to class A11.2 in the PDR surface layers. This photochemical evolution is driven by the increased importance of FUV processing in the PDR surface layers, resulting in a “weeding out” of the weakest links of the PAH family in these layers. For now, these JWST observations are consistent with a model in which the underlying PAH family is composed of a few species: the so-called ‘grandPAHs’.
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  • Habart, Emilie, et al. (author)
  • PDRs4All II. JWST’s NIR and MIR imaging view of the Orion Nebula
  • 2024
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 685
  • Journal article (peer-reviewed)abstract
    • Context. The James Webb Space Telescope (JWST) has captured the most detailed and sharpest infrared (IR) images ever taken of the inner region of the Orion Nebula, the nearest massive star formation region, and a prototypical highly irradiated dense photo-dissociation region (PDR). Aims. We investigate the fundamental interaction of far-ultraviolet (FUV) photons with molecular clouds. The transitions across the ionization front (IF), dissociation front (DF), and the molecular cloud are studied at high-angular resolution. These transitions are relevant to understanding the effects of radiative feedback from massive stars and the dominant physical and chemical processes that lead to the IR emission that JWST will detect in many Galactic and extragalactic environments. Methods. We utilized NIRCam and MIRI to obtain sub-arcsecond images over ∼150′′ and 42′′ in key gas phase lines (e.g., Pa α, Br α, [FeII] 1.64 µm, H2 1–0 S(1) 2.12 µm, 0–0 S(9) 4.69 µm), aromatic and aliphatic infrared bands (aromatic infrared bands at 3.3–3.4 µm, 7.7, and 11.3 µm), dust emission, and scattered light. Their emission are powerful tracers of the IF and DF, FUV radiation field and density distribution. Using NIRSpec observations the fractional contributions of lines, AIBs, and continuum emission to our NIRCam images were estimated. A very good agreement is found for the distribution and intensity of lines and AIBs between the NIRCam and NIRSpec observations. Results. Due to the proximity of the Orion Nebula and the unprecedented angular resolution of JWST, these data reveal that the molecular cloud borders are hyper structured at small angular scales of ∼0.1–1′′ (∼0.0002–0.002 pc or ∼40–400 au at 414 pc). A diverse set of features are observed such as ridges, waves, globules and photoevaporated protoplanetary disks. At the PDR atomic to molecular transition, several bright features are detected that are associated with the highly irradiated surroundings of the dense molecular condensations and embedded young star. Toward the Orion Bar PDR, a highly sculpted interface is detected with sharp edges and density increases near the IF and DF. This was predicted by previous modeling studies, but the fronts were unresolved in most tracers. The spatial distribution of the AIBs reveals that the PDR edge is steep and is followed by an extensive warm atomic layer up to the DF with multiple ridges. A complex, structured, and folded H0/H2 DF surface was traced by the H2 lines. This dataset was used to revisit the commonly adopted 2D PDR structure of the Orion Bar as our observations show that a 3D “terraced” geometry is required to explain the JWST observations. JWST provides us with a complete view of the PDR, all the way from the PDR edge to the substructured dense region, and this allowed us to determine, in detail, where the emission of the atomic and molecular lines, aromatic bands, and dust originate. Conclusions. This study offers an unprecedented dataset to benchmark and transform PDR physico-chemical and dynamical models for the JWST era. A fundamental step forward in our understanding of the interaction of FUV photons with molecular clouds and the role of FUV irradiation along the star formation sequence is provided.
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  • Peeters, Els, et al. (author)
  • PDRs4All: III. JWST's NIR spectroscopic view of the Orion Bar
  • 2024
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 685
  • Journal article (peer-reviewed)abstract
    • Context. JWST has taken the sharpest and most sensitive infrared (IR) spectral imaging observations ever of the Orion Bar photodis-sociation region (PDR), which is part of the nearest massive star-forming region the Orion Nebula, and often considered to be the 'prototypical'strongly illuminated PDR. Aims. We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the H II region to the atomic PDR -crossing the ionisation front (IF) -, and the subsequent transition to the molecular PDR -crossing the dissociation front (DF). Given the prevalence of PDRs in the interstellar medium and their dominant contribution to IR radiation, understanding the response of the PDR gas to far-ultraviolet (FUV) photons and the associated physical and chemical processes is fundamental to our understanding of star and planet formation and for the interpretation of any unresolved PDR as seen by JWST. Methods. We used high-resolution near-IR integral field spectroscopic data from NIRSpec on JWST to observe the Orion Bar PDR as part of the PDRs4All JWST Early Release Science programme. We constructed a 3″ × 25″ spatio-spectral mosaic covering 0.97-5.27 μm at a spectral resolution R of ~2700 and an angular resolution of 0.075″-0.173″. To study the properties of key regions captured in this mosaic, we extracted five template spectra in apertures centred on the three H2 dissociation fronts, the atomic PDR, and the H II region. This wealth of detailed spatial-spectral information was analysed in terms of variations in the physical conditions-incident UV field, density, and temperature -of the PDR gas. Results. The NIRSpec data reveal a forest of lines including, but not limited to, He I, H I, and C I recombination lines; ionic lines (e.g. Fe III and Fe II); O I and N I fluorescence lines; aromatic infrared bands (AIBs, including aromatic CH, aliphatic CH, and their CD counterparts); pure rotational and ro-vibrational lines from H2; and ro-vibrational lines from HD, CO, and CH+, with most of them having been detected for the first time towards a PDR. Their spatial distribution resolves the H and He ionisation structure in the Huygens region, gives insight into the geometry of the Bar, and confirms the large-scale stratification of PDRs. In addition, we observed numerous smaller-scale structures whose typical size decreases with distance from θ1 Ori C and IR lines from C I, if solely arising from radiative recombination and cascade, reveal very high gas temperatures (a few 1000 K) consistent with the hot irradiated surface of small-scale dense clumps inside the PDR. The morphology of the Bar, in particular that of the H2 lines, reveals multiple prominent filaments that exhibit different characteristics. This leaves the impression of a 'terraced'transition from the predominantly atomic surface region to the CO-rich molecular zone deeper in. We attribute the different characteristics of the H2 filaments to their varying depth into the PDR and, in some cases, not reaching the C+/C/CO transition. These observations thus reveal what local conditions are required to drive the physical and chemical processes needed to explain the different characteristics of the DFs and the photochemical evolution of the AIB carriers. Conclusions. This study showcases the discovery space created by JWST to further our understanding of the impact radiation from young stars has on their natal molecular cloud and proto-planetary disk, which touches on star and planet formation as well as galaxy evolution.
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  • Langlois, M., et al. (author)
  • The SPHERE infrared survey for exoplanets (SHINE) : II. Observations, data reduction and analysis, detection performances, and initial results
  • 2021
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 651
  • Journal article (peer-reviewed)abstract
    • Context. In recent decades, direct imaging has confirmed the existence of substellar companions (exoplanets or brown dwarfs) on wide orbits (>10 au) around their host stars. In striving to understand their formation and evolution mechanisms, in 2015 we initiated the SPHERE infrared survey for exoplanets (SHINE), a systematic direct imaging survey of young, nearby stars that is targeted at exploring their demographics.Aims. We aim to detect and characterize the population of giant planets and brown dwarfs beyond the snow line around young, nearby stars. Combined with the survey completeness, our observations offer the opportunity to constrain the statistical properties (occurrence, mass and orbital distributions, dependency on the stellar mass) of these young giant planets.Methods. In this study, we present the observing and data analysis strategy, the ranking process of the detected candidates, and the survey performances for a subsample of 150 stars that are representative of the full SHINE sample. Observations were conducted in a homogeneous way between February 2015 and February 2017 with the dedicated ground-based VLT/SPHERE instrument equipped with the IFS integral field spectrograph and the IRDIS dual-band imager, covering a spectral range between 0.9 and 2.3 μm. We used coronographic, angular, and spectral differential imaging techniques to achieve the best detection performances for this study, down to the planetary mass regime.Results. We processed, in a uniform manner, more than 300 SHINE observations and datasets to assess the survey typical sensitivity as a function of the host star and of the observing conditions. The median detection performance reached 5σ-contrasts of 13 mag at 200 mas and 14.2 mag at 800 mas with the IFS (YJ and YJH bands), and of 11.8 mag at 200 mas, 13.1 mag at 800 mas, and 15.8 mag at 3 as with IRDIS in H band, delivering one of the deepest sensitivity surveys thus far for young, nearby stars. A total of sixteen substellar companions were imaged in this first part of SHINE: seven brown dwarf companions and ten planetary-mass companions.These include two new discoveries, HIP 65426 b and HIP 64892 B, but not the planets around PDS70 that had not been originally selected for the SHINE core sample. A total of 1483 candidates were detected, mainly in the large field of view that characterizes IRDIS. The color-magnitude diagrams, low-resolution spectrum (when available with IFS), and follow-up observations enabled us to identify the nature (background contaminant or comoving companion) of about 86% of our subsample. The remaining cases are often connected to crowded-field follow-up observations that were missing. Finally, even though SHINE was not initially designed for disk searches, we imaged twelve circumstellar disks, including three new detections around the HIP 73145, HIP 86598, and HD 106906 systems.Conclusions. Nowadays, direct imaging provides a unique opportunity to probe the outer part of exoplanetary systems beyond 10 au to explore planetary architectures, as highlighted by the discoveries of: one new exoplanet, one new brown dwarf companion, and three new debris disks during this early phase of SHINE. It also offers the opportunity to explore and revisit the physical and orbital properties of these young, giant planets and brown dwarf companions (relative position, photometry, and low-resolution spectrum in near-infrared, predicted masses, and contrast in order to search for additional companions). Finally, these results highlight the importance of finalizing the SHINE systematic observation of about 500 young, nearby stars for a full exploration of their outer part to explore the demographics of young giant planets beyond 10 au and to identify the most interesting systems for the next generation of high-contrast imagers on very large and extremely large telescopes.
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  • Berne, Olivier, et al. (author)
  • PDRs4All : A JWST Early Release Science Program on Radiative Feedback from Massive Stars
  • 2022
  • In: Publications of the Astronomical Society of the Pacific. - : IOP Publishing. - 0004-6280 .- 1538-3873. ; 134:1035
  • Journal article (peer-reviewed)abstract
    • Massive stars disrupt their natal molecular cloud material through radiative and mechanical feedback processes. These processes have profound effects on the evolution of interstellar matter in our Galaxy and throughout the universe, from the era of vigorous star formation at redshifts of 1-3 to the present day. The dominant feedback processes can be probed by observations of the Photo-Dissociation Regions (PDRs) where the far-ultraviolet photons of massive stars create warm regions of gas and dust in the neutral atomic and molecular gas. PDR emission provides a unique tool to study in detail the physical and chemical processes that are relevant for most of the mass in inter- and circumstellar media including diffuse clouds, proto-planetary disks, and molecular cloud surfaces, globules, planetary nebulae, and star-forming regions. PDR emission dominates the infrared (IR) spectra of star-forming galaxies. Most of the Galactic and extragalactic observations obtained with the James Webb Space Telescope (JWST) will therefore arise in PDR emission. In this paper we present an Early Release Science program using the MIRI, NIRSpec, and NIRCam instruments dedicated to the observations of an emblematic and nearby PDR: the Orion Bar. These early JWST observations will provide template data sets designed to identify key PDR characteristics in JWST observations. These data will serve to benchmark PDR models and extend them into the JWST era. We also present the Science-Enabling products that we will provide to the community. These template data sets and Science-Enabling products will guide the preparation of future proposals on star-forming regions in our Galaxy and beyond and will facilitate data analysis and interpretation of forthcoming JWST observations.
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  • Marlin, R, et al. (author)
  • Targeting SARS-CoV-2 receptor-binding domain to cells expressing CD40 improves protection to infection in convalescent macaques
  • 2021
  • In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1, s. 5215-
  • Journal article (peer-reviewed)abstract
    • Achieving sufficient worldwide vaccination coverage against SARS-CoV-2 will require additional approaches to currently approved viral vector and mRNA vaccines. Subunit vaccines may have distinct advantages when immunizing vulnerable individuals, children and pregnant women. Here, we present a new generation of subunit vaccines targeting viral antigens to CD40-expressing antigen-presenting cells. We demonstrate that targeting the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein to CD40 (αCD40.RBD) induces significant levels of specific T and B cells, with long-term memory phenotypes, in a humanized mouse model. Additionally, we demonstrate that a single dose of the αCD40.RBD vaccine, injected without adjuvant, is sufficient to boost a rapid increase in neutralizing antibodies in convalescent non-human primates (NHPs) exposed six months previously to SARS-CoV-2. Vaccine-elicited antibodies cross-neutralize different SARS-CoV-2 variants, including D614G, B1.1.7 and to a lesser extent B1.351. Such vaccination significantly improves protection against a new high-dose virulent challenge versus that in non-vaccinated convalescent animals.
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  • van Gils, C H, et al. (author)
  • Consumption of vegetables and fruits and risk of breast cancer
  • 2005
  • In: JAMA: The Journal of the American Medical Association. - 1538-3598. ; 293:2, s. 183-193
  • Journal article (peer-reviewed)abstract
    • Context The intake of vegetables and fruits has been thought to protect against breast cancer. Most of the evidence comes from case-control studies, but a recent pooled analysis of the relatively few published cohort studies suggests no significantly reduced breast cancer risk is associated with vegetable and fruit consumption. Objective To examine the relation between total and specific vegetable and fruit intake and the incidence of breast cancer. Design, Setting, and Participants Prospective study of 285526 women between the ages of 25 and 70 years, participating in the European Prospective Investigation Into Cancer and Nutrition (EPIC) study, recruited from 8 of the 10 participating European countries. Participants completed a dietary questionnaire in 1992-1998 and were followed up for incidence of cancer until 2002. Main Outcome Measures Relative risks for breast cancer by total and specific vegetable and fruit intake. Analyses were stratified by age at recruitment and study center. Relative risks were adjusted for established breast cancer risk factors. Results During 1486402 person-years (median duration of follow-up, 5.4 years), 3659 invasive incident breast cancer cases were reported. No significant associations between vegetable or fruit intake and breast cancer risk were observed. Relative risks for the highest vs the lowest quintile were 0.98 (95% confidence interval [CI], 0.84-1.14) for total vegetables, 1.09 (95% Cl, 0.94-1.25) for total fruit, and 1.05 (95% Cl, 0.92-1.20) for fruit and vegetable juices. For 6 specific vegetable subgroups no associations with breast cancer risk were observed either. Conclusion Although the period of follow-up is limited for now, the results suggest that total or specific vegetable and fruit intake is not associated with risk for breast cancer.
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  • Berné, O., et al. (author)
  • A far-ultraviolet-driven photoevaporation flow observed in a protoplanetary disk
  • 2024
  • In: Science. - 0036-8075 .- 1095-9203. ; 383:6686, s. 988-992
  • Journal article (peer-reviewed)abstract
    • Most low-mass stars form in stellar clusters that also contain massive stars, which are sources of far-ultraviolet (FUV) radiation. Theoretical models predict that this FUV radiation produces photodissociation regions (PDRs) on the surfaces of protoplanetary disks around low-mass stars, which affects planet formation within the disks. We report James Webb Space Telescope and Atacama Large Millimeter Array observations of a FUV-irradiated protoplanetary disk in the Orion Nebula. Emission lines are detected from the PDR; modeling their kinematics and excitation allowed us to constrain the physical conditions within the gas. We quantified the mass-loss rate induced by the FUV irradiation and found that it is sufficient to remove gas from the disk in less than a million years. This is rapid enough to affect giant planet formation in the disk.
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  • Berné, O., et al. (author)
  • Formation of the methyl cation by photochemistry in a protoplanetary disk
  • 2023
  • In: Nature. - 0028-0836 .- 1476-4687. ; 621:7977, s. 56-59
  • Journal article (peer-reviewed)abstract
    • Forty years ago, it was proposed that gas-phase organic chemistry in the interstellar medium can be initiated by the methyl cation CH3+ (refs. 1–3), but so far it has not been observed outside the Solar System 4,5. Alternative routes involving processes on grain surfaces have been invoked 6,7. Here we report James Webb Space Telescope observations of CH3+ in a protoplanetary disk in the Orion star-forming region. We find that gas-phase organic chemistry is activated by ultraviolet irradiation.
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  • Habart, Emilie, et al. (author)
  • High-angular-resolution NIR view of the Orion Bar revealed by Keck/NIRC2
  • 2023
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 673
  • Journal article (peer-reviewed)abstract
    • Context. Nearby photo-dissociation regions (PDRs), where the gas and dust are heated by the far-ultraviolet (FUV) irradiation emitted from stars, are ideal templates with which to study the main stellar feedback processes. Aims. With this study, we aim to probe the detailed structures at the interfaces between ionized, atomic, and molecular gas in the Orion Bar. This nearby prototypical strongly irradiated PDR are among the first targets of the James Webb Space Telescope (JWST) within the framework of the PDRs4All Early Release Science program. Methods. We employed the subarcsecond resolution accessible with Keck-II NIRC2 and its adaptive optics system to obtain images of the vibrationally excited line H2 1-0 S(1) at 2.12 μm that are more detailed and complete than ever before. H2 1-0 S(1) traces the dissociation front (DF), and the [FeII] and Brγ lines, at 1.64 and 2.16 μm, respectively, trace the ionization front (IF). The former is a powerful tracer of the FUV radiation field strength and gas density distribution at the PDR edge, while the last two trace the temperature and density distribution from the ionized gas to the PDR. We obtained narrow-band filter images in these key gas line diagnostics over ∼40″ at spatial scales of ∼0.1″ (∼0.0002 pc or ∼40 AU at 414 pc). Results. The Keck/Near Infrared Camera 2 (NIRC2) observations spatially resolve a plethora of irradiated substructures such as ridges, filaments, globules, and proplyds. This portends what JWST should accomplish and how it will complement the highest resolution Atacama Large Millimeter/submillimeter Array (ALMA) maps of the molecular cloud. We observe a remarkable spatial coincidence between the H2 1-0 S(1) vibrational and HCO+ J = 4-3 rotational emission previously obtained with ALMA. This likely indicates the intimate link between these two molecular species and highlights that in high-pressure PDRs, the H/H2 and C+/C/CO transitions zones come closer than in a typical layered structure of a constant density PDR. The H/H2 dissociation front appears as a highly structured region containing substructures with a typical thickness of a few ∼10-3 pc.
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  • Riboli, E, et al. (author)
  • European prospective investigation into cancer and nutrition (EPIC): study populations and data collection
  • 2002
  • In: Public Health Nutrition. - 1475-2727. ; 5:6B, s. 1113-1124
  • Journal article (peer-reviewed)abstract
    • The European Prospective Investigation into Cancer and. Nutrition (EPIC) is an ongoing multi-centre prospective cohort study designed to investigate the relationship between nutrition and cancer, with the potential for studying other diseases as well. The study currently includes 519 978 participants (366 521 women and 153457 men, mostly aged 35-70 years) in 23 centres located in 10 European countries, to be followed for cancer incidence and cause-specific mortality for several decades. At enrolment, which took place between 1992 and 2000 at each of the different centres, information was collected through a non-dietary questionnaire on lifestyle variables and through a dietary questionnaire addressing usual diet. Anthropometric measurements were performed and blood samples taken, from which plasma, serum, red cells and buffy coat fractions were separated and aliquoted for long-term storage, mostly in liquid nitrogen. To calibrate dietary measurements, a standardised, computer-assisted 24-hour dietary recall was implemented at each centre on stratified random samples of the participants, for a total of 36 900 subjects. EPIC represents the largest single resource available today world-wide for prospective investigations on the aetiology of cancers (and other diseases) that can integrate questionnaire data on lifestyle and diet, biomarkers of diet and of endogenous metabolism (e.g. hormones and growth factors) and genetic polymorphisms. First results of case-control studies nested within the cohort are expected early in 2003. The present paper provides a description of the EPIC study, with the aim of simplifying reference to it in future papers reporting substantive or methodological studies carried out in the EPIC cohort.
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  • Elyajouri, Meriem, et al. (author)
  • PDRs4All V. Modelling the dust evolution across the illuminated edge of the Orion Bar
  • 2024
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 685
  • Journal article (peer-reviewed)abstract
    • Context. Interstellar dust particles, in particular carbonaceous nano-grains (like polycyclic aromatic hydrocarbons, fullerenes, and amorphous hydrogenated carbon), are critical players for the composition, energy budget, and dynamics of the interstellar medium (ISM). The dust properties, specifically the composition and size of dust grains are not static; instead, they exhibit considerable evolution triggered by variations in local physical conditions such as the density and gas temperature within the ISM, as is the case in photon-dominated regions (PDRs). The evolution of dust and its impact on the local physical and chemical conditions is thus a key question for understanding the first stages of star formation. Aims. From the extensive spectral and imaging data of the JWST PDRs4All program, we study the emission of dust grains within the Orion Bar – a well-known, highly far-UV (FUV)-irradiated PDR situated at the intersection between cold, dense molecular clouds, and warm ionized regions. The Orion Bar because of its edge-on geometry provides an exceptional benchmark for characterizing dust evolution and the associated driving processes under varying physical conditions. Our goal is to constrain the local properties of dust by comparing its emission to models. Taking advantage of the recent JWST data, in particular the spectroscopy of dust emission, we identify new constraints on dust and further previous works of dust modelling. Methods. To characterize interstellar dust across the Orion Bar, we follow its emission as traced by JWST NIRCam (at 3.35 and 4.8 µm) and MIRI (at 7.7, 11.3, 15.0, and 25.5 µm) broad band images, along with NIRSpec and MRS spectroscopic observations. First, we constrain the minimum size and hydrogen content of carbon nano-grains from a comparison between the observed dust emission spectra and the predictions of the Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS) coupled to the numerical code DustEM. Using this dust model, we then perform 3D radiative transfer simulations of dust emission with the SOC code (Scattering with OpenCL) and compare to data obtained along well chosen profiles across the Orion Bar. Results. The JWST data allows us, for the first time, to spatially resolve the steep variation of dust emission at the illuminated edge of the Orion Bar PDR. By considering a dust model with carbonaceous nano-grains and submicronic coated silicate grains, we derive unprecedented constraints on the properties of across the Orion Bar. To explain the observed emission profiles with our simulations, we find that the nano-grains must be strongly depleted with an abundance (relative to the gas) 15 times less than in the diffuse ISM. The NIRSpec and MRS spectroscopic observations reveal variations in the hydrogenation of the carbon nano-grains. The lowest hydrogenation levels are found in the vicinity of the illuminating stars suggesting photo-processing while more hydrogenated nano-grains are found in the cold and dense molecular region, potentially indicative of larger grains.
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27.
  • Engeset, D, et al. (author)
  • Fish consumption and breast cancer risk. The European Prospective Investigation into Cancer and Nutrition (EPIC)
  • 2006
  • In: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 119:1, s. 175-182
  • Journal article (peer-reviewed)abstract
    • There is current interest in fish consumption and marine omega-3 (n-3) fatty acids and breast cancer risk. Some in vitro and animal studies have suggested an inhibitory effect of marine n-3 fatty acids on breast cancer growth, but the results from epidemiological studies that have examined the association between fish consumption and breast cancer risk in humans are inconsistent. We examined fish consumption and breast cancer risk in 310,671 women aged between 25 and 70 yr at recruitment into the European Prospective Investigation Into Cancer and Nutrition (EPIC). The participants completed a dietary questionnaire between 1992-98 and were followed up for incidence of breast cancer for a median of 6.4 yr. Hazard ratio for breast cancer by intake of total and lean and fatty fish were estimated, stratified by study centre and adjusted for established breast cancer risk factors. During follow-up, 4,776 invasive incident breast cancers were reported. No significant associations between intake of total fish and breast cancer risk were observed, hazard ratio (HR) 1.01 (95% confidence interval [CI] 0.99-1.02; p = 0.28 per 10 g fish/day). When examining lean and ratty fish separately, we round a positive significant association only in the highest quintile for fatty fish (HR 1.13, 95% CI 1.01-1.26), but test for trend was not significant (p = 0.10). No associations with breast cancer risk were observed when the study participants were subdivided by menopausal status. Although the period of follow-up is relatively short, the results provide no evidence for an association between fish intake and breast cancer risk. (c) 2006 Wiley-Liss, Inc.
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28.
  • Hernández-Vera, C., et al. (author)
  • The extremely sharp transition between molecular and ionized gas in the Horsehead nebula
  • 2023
  • In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 677
  • Journal article (peer-reviewed)abstract
    • Massive stars can determine the evolution of molecular clouds by eroding and photo-evaporating their surfaces with strong ultraviolet (UV) radiation fields. Moreover, UV radiation is relevant in setting the thermal gas pressure in star-forming clouds, whose influence can extend across various spatial scales, from the rims of molecular clouds to entire star-forming galaxies. Probing the fundamental structure of nearby molecular clouds is therefore crucial to understand how massive stars shape their surrounding medium and how fast molecular clouds are destroyed, specifically at their UV-illuminated edges, where models predict an intermediate zone of neutral atomic gas between the molecular cloud and the surrounding ionized gas whose size is directly related to the exposed physical conditions. We present the highest angular resolution (0.≥ 5, corresponding to 207 au) and velocity-resolved images of the molecular gas emission in the Horsehead nebula, using CO J = 3- 2 and HCO+ J = 4- 3 observations with the Atacama Large Millimeter/submillimeter Array (ALMA). We find that CO and HCO+ are present at the edge of the cloud, very close to the ionization (H+/H) and dissociation fronts (H/H2), suggesting a very thin layer of neutral atomic gas (<650 au) and a small amount of CO-dark gas (AV = 0.006- 0.26 mag) for stellar UV illumination conditions typical of molecular clouds in the Milky Way. The new ALMA observations reveal a web of molecular gas filaments with an estimated thermal gas pressure of Pth = (2.3 - 4.0) - 106 K cm- 3, and the presence of a steep density gradient at the cloud edge that can be well explained by stationary isobaric photo-dissociation region (PDR) models with pressures consistent with our estimations. However, in the H≥ ¯II region and PDR interface, we find Pth,PDR > Pth,H≥ ¯II suggesting the gas is slightly compressed. Therefore, dynamical effects cannot be completely ruled out and even higher angular observations will be needed to unveil their role.
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29.
  • Lacour, S., et al. (author)
  • The limb-darkened Arcturus : imaging with the IOTA/IONIC interferometer
  • 2008
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 485:2, s. 561-570
  • Journal article (peer-reviewed)abstract
    • Aims. We undertook an H band interferometric examination of Arcturus, a star frequently used as a spatial and spectral calibrator. Methods. Using the IOTA 3 telescope interferometer, we performed spectro-interferometric observations (R approximate to 35) of Arcturus. Atmospheric models and prescriptions were fitted to the data to derive the brightness distribution of the photosphere. Image reconstruction was performed using two software algorithms: WISARD and MIRA. Results. An achromatic power law proved to be a good model of the brightness distribution, with a limb darkening compatible with the one derived from atmospheric model simulations using our mARCS model. A Rosseland diameter of 21.05 +/- 0.21 was derived, corresponding to an effective temperature of T-eff = 4295 +/- 26 K. No companion was detected from the closure phases, with an upper limit on the brightness ratio of 8 x 10(-4) at 1 AU. The dynamic range at such distance from the photosphere was established as 1.5 x 10(-4) (1 sigma rms). An upper limit of 1.7 x 10(-3) was also derived for the level of brightness asymmetries present in the photosphere.
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30.
  • Linseisen, J, et al. (author)
  • Consumption of added fats and oils in the European Prospective Investigation into Cancer and Nutrition (EPIC) centres across 10 European countries as assessed by 24-hour dietary recalls
  • 2002
  • In: Public Health Nutrition. - 1475-2727. ; 5:6B, s. 1227-1242
  • Journal article (peer-reviewed)abstract
    • Objective: To evaluate the consumption of added fats and oils across the European centres and countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). Design and setting: 24-Hour dietary recalls were collected by means of standardised computer-guided interviews in 27 redefined EPIC centres across 10 European countries. Subjects: From an initial number of 36 900 subjects, single dietary recalls from 22 924 women and 13 031 men in the age range of 35-74 years were included. Results: Mean daily intake of added fats and oils varied between 16.2 g (Varese, Italy) and 41.1 g (Malmo, Sweden) in women and between 24.7 g (Ragusa, Italy) and 66.0 g (Potsdam, Germany) in men. Total mean lipid intake by consumption of added fats and oils, including those used for sauce preparation, ranged between 18.3 (Norway) and 37.2 g day(-1) (Greece) in women and 28.4 (Heidelberg, Germany) and 51.2 g day(-1) (Greece) in men. The Mediterranean EPIC centres with high olive oil consumption combined with low animal fat intake contrasted with the central and northern European centres where fewer vegetable oils, more animal fats and a high proportion of margarine were consumed. The consumption of added fats and oils of animal origin was highest in the German EPIC centres, followed by the French. The contribution of added fats and oils to total energy intake ranged from 8% in Norway to 22% in Greece. Conclusions: The results demonstrate a high variation in dietary intake of added fats Oil and oils in EPIC, providing a good opportunity to elucidate the role of dietary fats in cancer aetiology.
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31.
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32.
  • Mitrou, Panagiota N., et al. (author)
  • Mediterranean dietary pattern and prediction of all-cause mortality in a US population - Results from the NIH-AARP diet and health study
  • 2007
  • In: Archives of Internal Medicine. - 0003-9926. ; 167:22, s. 2461-2468
  • Journal article (peer-reviewed)abstract
    • Background: The Mediterranean diet has been suggested to play a beneficial role for health and longevity. However, to our knowledge, no prospective US study has investigated the Mediterranean dietary pattern in relation to mortality. Methods: Study participants included 214 284 men and 166 012 women in the National Institutes of Health (NIH)-AARP ( formerly known as the American Association of Retired Persons) Diet and Health Study. During follow-up for all-cause mortality (1995-2005), 27 799 deaths were documented. In the first 5 years of follow-up, 5985 cancer deaths and 3451 cardiovascular disease (CVD) deaths were reported. We used a 9-point score to assess conformity with the Mediterranean dietary pattern ( components included vegetables, legumes, fruits, nuts, whole grains, fish, monounsaturated fat saturated fat ratio, alcohol, and meat). We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) using age- and multivariate-adjusted Cox models. Results: The Mediterranean diet was associated with reduced all-cause and cause-specific mortality. In men, the multivariate HRs comparing high to low conformity for all-cause, CVD, and cancer mortality were 0.79 ( 95% CI, 0.76-0.83), 0.78 ( 95% CI, 0.69-0.87), and 0.83 ( 95% CI, 0.76-0.91), respectively. In women, an inverse association was seen with high conformity with this pattern: decreased risks that ranged from 12% for cancer mortality to 20% for all-cause mortality (P=.04 and P <.001, respectively, for the trend). When we restricted our analyses to never smokers, associations were virtually unchanged. Conclusion: These results provide strong evidence for a beneficial effect of higher conformity with the Mediterranean dietary pattern on risk of death from all causes, including deaths due to CVD and cancer, in a US population.
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33.
  • Sieri, Sabina, et al. (author)
  • Dietary fat and breast cancer risk in the European Prospective Investigation into Cancer and Nutrition.
  • 2008
  • In: American Journal of Clinical Nutrition. - : Elsevier BV. - 0002-9165 .- 1938-3207. ; 88:5, s. 1304-1312
  • Journal article (peer-reviewed)abstract
    • BACKGROUND:Epidemiologic studies have produced conflicting results with respect to an association of dietary fat with breast cancer.OBJECTIVE:We aimed to investigate the association between fat consumption and breast cancer.DESIGN:We prospectively investigated fat consumption in a large (n = 319,826), geographically and culturally heterogeneous cohort of European women enrolled in the European Prospective Investigation into Cancer and Nutrition who completed a dietary questionnaire. After a mean of 8.8 y of follow-up, 7119 women developed breast cancer. Cox proportional hazard models, stratified by age and center and adjusted for energy intake and confounders, were used to estimate hazard ratios (HRs) for breast cancer.RESULTS:An association between high saturated fat intake and greater breast cancer risk was found [HR = 1.13 (95% CI: 1.00, 1.27; P for trend = 0.038) for the highest quintile of saturated fat intake compared with the lowest quintile: 1.02 (1.00, 1.04) for a 20% increase in saturated fat consumption (continuous variable)]. No significant association of breast cancer with total, monounsaturated, or polyunsaturated fat was found, although trends were for a direct association of risk with monounsaturated fat and an inverse association with polyunsaturated fat. In menopausal women, the positive association with saturated fat was confined to nonusers of hormone therapy at baseline [1.21 (0.99, 1.48) for the highest quintile compared with the lowest quintile; P for trend = 0.044; and 1.03 (1.00, 1.07) for a 20% increase in saturated fat as a continuous variable].CONCLUSIONS:Evidence indicates a weak positive association between saturated fat intake and breast cancer risk. This association was more pronounced for postmenopausal women who never used hormone therapy.
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34.
  • Sieri, S, et al. (author)
  • Patterns of alcohol consumption in 10 European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) project
  • 2002
  • In: Public Health Nutrition. - 1475-2727. ; 5:6B, s. 1287-1296
  • Journal article (peer-reviewed)abstract
    • Objective. The aim of this study was to compare the quantities of alcohol and types of alcoholic beverages consumed, and the timing of consumption, in centres participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). These centres, in 10 European countries, are characterised by widely differing drinking habits and frequencies of alcohol-related diseases. Methods: We collected a single standardised 24-hour dietary recall per subject from a random sample of the EPIC cohort (36 900 persons initially and 35 955 after exclusion of subjects under 35 and over 74 years of age). This provided detailed information on the distribution of alcohol consumption during the day in relation to main meals, and was used to determine weekly consumption patterns. The crude and adjusted (by age, day of week and season) means of total ethanol consumption and consumption according to type of beverage were stratified by centre and sex. Results: Sex was a strong determinant of drinking patterns in all 10 countries. The highest total alcohol consumption was observed in the Spanish centres (San Sebastian, 41.4 g day(-1)) for men and in Danish centres (Copenhagen, 20.9 g day(-1)) for women. The lowest total alcohol intake was in the Swedish centres (Umea, 10.2 g day(-1)) in men and in Greek women (3.4 g day(-1)). Among men, the main contributor to total alcohol intake was wine in Mediterranean countries and beer in the Dutch, German, Swedish and Danish centres. In most centres, the main source of alcohol for women was wine except for Murcia (Spain), where it was beer. Alcohol consumption, particularly by women, increased markedly during the weekend in nearly all centres. The German, Dutch, UK (general population) and Danish centres were characterised by the highest percentages of alcohol consumption outside mealtimes. Conclusions: The large variation in drinking patterns among the EPIC centres provides an opportunity to better understand the relationship between alcohol and alcohol-related diseases.
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35.
  • Thiébaut, R., et al. (author)
  • TNFSF15 polymorphisms are associated with susceptibility to inflammatory bowel disease in a new European cohort
  • 2009
  • In: American Journal of Gastroenterology. - : Ovid Technologies (Wolters Kluwer Health). - 0002-9270 .- 1572-0241. ; 104:2, s. 384-391
  • Journal article (peer-reviewed)abstract
    • OBJECTIVES: Inflammatory bowel disease (IBD), e.g., Crohn's disease (CD) and ulcerative colitis (UC), is a complex genetic disorder. Tumor necrosis factor (ligand) superfamily, member 15 (TNFSF15) has been previously identified as a susceptibility gene for CD in Japanese and UK cohorts. This replication study was designed in order to confirm and further validate the role of TNFSF15 in IBD. METHODS: A total of 666 IBD families (corresponding to 2,982 relatives) with European ancestry were genotyped for the rs6478108 and rs7869487 polymorphisms, which define the main TNFSF15 haplotypes previously associated with CD. An association between the main haplotypes and CD, UC and IBD was tested using the Genehunter TDT and Unphased statistics. Caspase recruitment domain 15 (CARD15)/TNFSF15 interaction and genotype/phenotype correlations were also studied. RESULTS: The previously reported "high-risk" haplotype (A) was associated with IBD (P=0.001) (OR=1.25 (1.05-1.50)) and CD (P=0.02) (OR=1.31 (1.03-1.67)) whereas the "protective" (B) haplotype was significantly less transmitted to IBD and CD patients. No interaction between CARD15 and TNFSF15 was detected. We also failed to define a clinical subgroup of CD patients specifically associated with TNFSF15 haplotype A. CONCLUSIONS: This study confirms that TNFSF15 or a closely linked gene is involved in the genetic predisposition to CD.
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36.
  • Tjonneland, Anne, et al. (author)
  • Alcohol intake and breast cancer risk: the European Prospective Investigation into Cancer and Nutrition (EPIC)
  • 2007
  • In: Cancer Causes and Control. - : Springer Science and Business Media LLC. - 1573-7225 .- 0957-5243. ; 18:4, s. 361-373
  • Journal article (peer-reviewed)abstract
    • Objective Most epidemiologic studies have suggested an increased risk of breast cancer with increasing alcohol intake. Using data from 274,688 women participating in the European Prospective Investigation into Cancer and Nutrition study (EPIC), we investigated the relation between alcohol intake and the risk of breast cancer. Methods Incidence rate ratios (IRRs) based on Cox proportional hazard models were calculated using reported intake of alcohol, recent (at baseline) and lifetime exposure. We adjusted for known risk factors and stratified according to study center as well as potentially modifying host factors. Results During 6.4 years of follow up, 4,285 invasive cases of breast cancer within the age group 35-75 years were identified. For all countries together the IRR per 10 g/day higher recent alcohol intake (continuous) was 1.03 (95% confidence interval (CI): 1.01-1.05). When adjusted, no association was seen between lifetime alcohol intake and risk of breast cancer. No difference in risk was shown between users and non-users of HRT, and there was no significant interaction between alcohol intake and BMI, HRT or dietary folate. Conclusion This large European study supports previous findings that recent alcohol intake increases the risk of breast cancer.
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37.
  • Zannese, Marion, et al. (author)
  • OH as a probe of the warm-water cycle in planet-forming disks
  • 2024
  • In: Nature Astronomy. - 2397-3366. ; 8:5, s. 577-586
  • Journal article (peer-reviewed)abstract
    • Water is a key ingredient for the emergence of life as we know it. Yet, its destruction and reformation in space remain unprobed in warm gas (T > 300 K). Here we detect with the James Webb Space Telescope the emission of the hydroxyl radical (OH) from d203-506, a planet-forming disk exposed to external far-ultraviolet (FUV) radiation. These observations were made as part of the Early Release Science programme PDRs4All, which is focused on the Orion bar. The observed OH spectrum is compared with the results of quantum dynamical calculations to reveal two essential molecular processes. The highly excited rotational lines of OH in the mid-infrared are telltale signs of H2O destruction by FUV radiation. The OH rovibrational lines in the near-infrared are attributed to chemical excitation by the key reaction O + H-2 -> OH + H, which seeds the formation of water in the gas phase. These results show that under warm and irradiated conditions, water is destroyed and efficiently reformed through gas-phase reactions. We infer that, in this source, the equivalent of Earth oceans' worth of water is destroyed per month and replenished. This warm-water cycle could reprocess some water inherited from cold interstellar clouds and explain the lower deuterium fraction of water in Earth's oceans compared with that found around protostars.
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