| 1. |
- Algaba, Juan-Carlos, et al.
(författare)
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Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
- 2021
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 911:1
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Forskningsöversikt (refereegranskat)abstract
- In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M o˙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87's spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded.
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| 2. |
- Hellström, Mats, 1976, et al.
(författare)
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Bioengineered uterine tissue supports pregnancy in a rat model
- 2016
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Ingår i: Fertility and Sterility. - : Elsevier BV. - 0015-0282. ; 106:2
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To create a bioengineered uterine patch for uterine repair of a partially defect uterus. Design: Three different decellularized uterine scaffolds were recellularized in vitro with primary uterine cells and green fluorescent protein-(GPF-) labeled bone marrow-derived mesenchymal stem cells (GFP-MSCs). The patches were transplanted in vivo to investigate their tissue adaptation and supporting capacity during pregnancy. Animal(s): Female Lewis rats (n = 9) as donors to generate whole-uterus scaffolds using three different protocols (n = 3 per protocol); Sprague Dawley rats (n = 40) for primary uterus cell isolation procedures (n = 10) and for transplantation/pregnancy studies (n = 30); and male Sprague Dawley rats (n = 12) for mating. Intervention(s): Decellularization was achieved by whole-uterus perfusion with buffered or nonbuffered Triton-X100 and dimethyl sulfoxide (DMSO; group P1/P2) or with sodium deoxycholate (group P3). Primary uterine cells and GFP-MSCs were used to develop uterine tissue constructs, which were grafted to uteri with partial tissue defects. Main Outcome Measure(s): Recellularization efficiency and graft quality were analyzed morphologically, immunohistochemically, and by real-time quantitative polymerase chain reaction (PCR). The location and number of fetuses were documented during pregnancy days 16-20. Result(s): Pregnancy and fetal development were normal in groups P1 and P2, with fetal development over patched areas. Group P3 showed significant reduction of fetal numbers, and embryos were not seen in the grafted area. Quantitative PCR and immunohistochemistry revealed uterus-like tissue in the patches, which had been further reconstructed by infiltrating host cells after transplantation. Conclusion(s): Primary uterine cells and MSCs can be used to reconstruct decellularized uterine tissue. The bioengineered patches made from triton-X100+DMSO-generated scaffolds were supportive during pregnancy. These protocols should be explored further to develop suitable grafting material to repair partially defect uteri and possibly to create a complete bioengineered uterus. ((C) 2016 by American Society for Reproductive Medicine.)
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