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PubMed · 17170289

Comet 81P/Wild 2 under a microscope.

Don Brownlee·Peter Tsou·Jérôme Aléon·Conel M O'd Alexander·Tohru Araki·Sasa Bajt·Giuseppe A Baratta·Ron Bastien·Phil Bland·Pierre Bleuet·Janet Borg·John P Bradley·Adrian Brearley·F Brenker·Sean Brennan·John C Bridges·Nigel D Browning·John R Brucato·E Bullock·Mark J Burchell·Henner Busemann·Anna Butterworth·Marc Chaussidon·Allan Cheuvront·Miaofang Chi·Mark J Cintala·B C Clark·Simon J Clemett·George Cody·Luigi Colangeli·George Cooper·Patrick Cordier·C Daghlian·Zurong Dai·Louis D'Hendecourt·Zahia Djouadi·Gerardo Dominguez·Tom Duxbury·Jason P Dworkin·Denton S Ebel·Thanasis E Economou·Sirine Fakra·Sam A J Fairey·Stewart Fallon·Gianluca Ferrini·T Ferroir·Holger Fleckenstein·Christine Floss·George Flynn·Ian A Franchi·Marc Fries·Z Gainsforth·J-P Gallien·Matt Genge·Mary K Gilles·Philipe Gillet·Jamie Gilmour·Daniel P Glavin·Matthieu Gounelle·Monica M Grady·Giles A Graham·P G Grant·Simon F Green·Faustine Grossemy·Lawrence Grossman·Jeffrey N Grossman·Yunbin Guan·Kenji Hagiya·Ralph Harvey·Philipp Heck·Gregory F Herzog·Peter Hoppe·Friedrich Hörz·Joachim Huth·Ian D Hutcheon·Konstantin Ignatyev·Hope Ishii·Motoo Ito·Damien Jacob·Chris Jacobsen·Stein Jacobsen·Steven Jones·David Joswiak·Amy Jurewicz·Anton T Kearsley·Lindsay P Keller·H Khodja·A L David Kilcoyne·Jochen Kissel·Alexander Krot·Falko Langenhorst·Antonio Lanzirotti·Loan Le·Laurie A Leshin·J Leitner·L Lemelle·Hugues Leroux·Ming-Chang Liu·K Luening·Ian Lyon

Abstract

The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.

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BibTeXRIS

Don Brownlee, Peter Tsou, Jérôme Aléon, Conel M O'd Alexander, Tohru Araki, Sasa Bajt, Giuseppe A Baratta, Ron Bastien, Phil Bland, Pierre Bleuet, Janet Borg, John P Bradley, Adrian Brearley, F Brenker, Sean Brennan, John C Bridges, Nigel D Browning, John R Brucato, E Bullock, Mark J Burchell, Henner Busemann, Anna Butterworth, Marc Chaussidon, Allan Cheuvront, Miaofang Chi, Mark J Cintala, B C Clark, Simon J Clemett, George Cody, Luigi Colangeli, George Cooper, Patrick Cordier, C Daghlian, Zurong Dai, Louis D'Hendecourt, Zahia Djouadi, Gerardo Dominguez, Tom Duxbury, Jason P Dworkin, Denton S Ebel, Thanasis E Economou, Sirine Fakra, Sam A J Fairey, Stewart Fallon, Gianluca Ferrini, T Ferroir, Holger Fleckenstein, Christine Floss, George Flynn, Ian A Franchi, Marc Fries, Z Gainsforth, J-P Gallien, Matt Genge, Mary K Gilles, Philipe Gillet, Jamie Gilmour, Daniel P Glavin, Matthieu Gounelle, Monica M Grady, Giles A Graham, P G Grant, Simon F Green, Faustine Grossemy, Lawrence Grossman, Jeffrey N Grossman, Yunbin Guan, Kenji Hagiya, Ralph Harvey, Philipp Heck, Gregory F Herzog, Peter Hoppe, Friedrich Hörz, Joachim Huth, Ian D Hutcheon, Konstantin Ignatyev, Hope Ishii, Motoo Ito, Damien Jacob, Chris Jacobsen, Stein Jacobsen, Steven Jones, David Joswiak, Amy Jurewicz, Anton T Kearsley, Lindsay P Keller, H Khodja, A L David Kilcoyne, Jochen Kissel, Alexander Krot, Falko Langenhorst, Antonio Lanzirotti, Loan Le, Laurie A Leshin, J Leitner, L Lemelle, Hugues Leroux, Ming-Chang Liu, K Luening, Ian Lyon. 2006-12-15. Comet 81P/Wild 2 under a microscope.. https://doi.org/10.1126/science.1135840

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BACKGROUND: Frailty is a major risk factor for influenza-related complications and can influence vaccine effectiveness. We aimed to assess the relative vaccine effectiveness (rVE) of high-dose (HD-IIV) versus standard-dose inactivated influenza vaccine (SD-IIV) in older adults aged 65 years or older according to frailty risk. METHODS: This study was a prespecified analysis of DANFLU-2, an open-label, individually randomised trial, conducted in Denmark during three consecutive influenza seasons (2022-23, 2023-24, and 2024-25). Adults aged 65 years or older were randomised (1:1) to the HD-IIV or SD-IIV group. The primary endpoint was hospitalisation for influenza or pneumonia. Frailty was defined according to the validated Hospital Frailty Risk Score (HFRS) based on ICD-10 codes within 10 years before randomisation. Participants were stratified into three HFRS categories, namely low (<5 points), intermediate (5-15 points), and high (>15 points) frailty risk. The rVE of HD-IIV versus SD-IIV against the primary endpoint was assessed across prespecified HFRS categories and treating HFRS as a continuous variable. Pearson's chi-square test was used to compare safety events across frailty risk groups and randomisation groups. FINDINGS: Among 332&#x2009;438 randomised participants (mean age 73&#xb7;7 years [SD 5&#xb7;8]; 161&#x2009;538 [48&#xb7;6%] were female), 276&#x2009;173 (83&#xb7;1%) had low frailty risk, 52&#x2009;395 (15&#xb7;8%) had intermediate frailty risk, and 3861 (1&#xb7;2%) had high frailty risk. The primary endpoint of hospitalisation for influenza or pneumonia occurred in 1424 (0&#xb7;5%) of 276&#x2009;173 participants with low frailty risk, 761 (1&#xb7;5%) of 52&#x2009;395 with intermediate frailty risk, and 163 (4&#xb7;2%) of 3861 with high frailty risk (relative risk [RR] for intermediate vs low frailty risk 2&#xb7;8 [95% CI 2&#xb7;6-3&#xb7;1]; RR for high vs low frailty risk 8&#xb7;2 [7&#xb7;0-9&#xb7;6]). HFRS as a continuous variable significantly modified the effect of HD-IIV versus SD-IIV against the primary endpoint with higher rVE estimates with increasing HFRS (pinteraction=0&#xb7;020). The rVE was 0&#xb7;2% (95% CI -10&#xb7;8 to 10&#xb7;2) among those with low frailty risk, 13&#xb7;1% (-0&#xb7;4 to 24&#xb7;8) among those with intermediate frailty risk, and 19&#xb7;9% (-10&#xb7;3 to 42&#xb7;1) among those with high frailty risk. No significant interaction was observed when HFRS was assessed according to the prespecified categorical frailty groups (pinteraction=0&#xb7;17). The proportion of participants with at least one serious adverse event increased across frailty risk groups (13&#x2009;366 [4&#xb7;8%] of 275&#x2009;795 for low frailty risk, 5475 [10&#xb7;5%] of 52&#x2009;315 for intermediate frailty risk, and 777 [20&#xb7;2%] of 3850 for high frailty risk; p<0&#xb7;0001), with similar proportions of serious adverse events in the HD-IIV and SD-IIV groups for each frailty risk group. INTERPRETATION: Among adults aged 65 years or older in Denmark, frailty risk might modify the effects of HD-IIV versus SD-IIV against hospitalisation for influenza or pneumonia, with higher rVE estimates with increasing frailty risk. These findings might support considering high-dose influenza vaccines for frail older adults. However, effect modification was not evident when frailty was assessed using prespecified categorical subgroups, and subgroup-specific estimates were imprecise, with 95% CIs crossing the null. These results should be considered exploratory, warranting further investigation. FUNDING: The DANFLU-2 trial was funded by Sanofi.

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