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The early optical emission of gamma-ray bursts (GRBs) gives an opportunity to understand the central engine and first stages of these events. About 30% of GRBs present flares whose origin is still a subject of discussion. We present optical photometry of GRB 180620A with the COATLI telescope and RATIR instrument. COATLI started to observe from the end of prompt emission at T + 39.3 s and RATIR from T + 121.4 s. We supplement the optical data with the X-ray light curve from Swift/XRT. We observe an optical flare from T + 110 s to T + 550 s, with a temporal index decay α O,decay = 1.32 ± 0.01, and Δt/t = 1.63, which we interpret as the signature of a reverse shock component. After the initial normal decay the light curves show a long plateau from T + 500 s to T + 7800 s in both X-rays and the optical before decaying again after an achromatic jet break at T + 7800 s. Fluctuations are seen during the plateau phase in the optical. Adding to the complexity of GRB afterglows, the plateau phase (typically associated with the coasting phase of the jet) is seen in this object after the "normal" decay phase (associated with the deceleration phase of the jet), and the jet break phase occurs directly after the plateau. We suggest that this sequence of events can be explained by a rapid deceleration of the jet with t d ≲ 40 s due to the high density of the environment (≈100 cm-3) followed by reactivation of the central engine, which causes the flare and powers the plateau phase.

We investigate the prompt emission and the afterglow properties of short-duration gamma-ray burst (sGRB) 130603B and another eight sGRB events during 2012-2015, observed by several multiwavelength facilities including the Gran Canarias Telescope 10.4 m telescope. Prompt emission high energy data of the events were obtained by INTEGRAL-SPI-ACS, Swift-BAT, and Fermi-GBM satellites. The prompt emission data by INTEGRAL in the energy range of 0.1-10 MeV for sGRB 130603B, sGRB 140606A, sGRB 140930B, sGRB 141212A, and sGRB 151228A do not show any signature of the extended emission or precursor activity and their spectral and temporal properties are similar to those seen in case of other short bursts. For sGRB 130603B, our new afterglow photometric data constrain the pre-jet-break temporal decay due to denser temporal coverage. For sGRB 130603B, the afterglow light curve, containing both our new and previously published photometric data is broadly consistent with the ISM afterglow model. Modeling of the host galaxies of sGRB 130603B and sGRB 141212A using the LePHARE software supports a scenario in which the environment of the burst is undergoing moderate star formation activity. From the inclusion of our late-time data for eight other sGRBs we are able to: place tight constraints on the non-detection of the afterglow, host galaxy, or any underlying 'kilonova' emission. Our late-time afterglow observations of the sGRB 170817A/GW170817 are also discussed and compared with the sub-set of sGRBs.

Wide-field optical surveys have begun to uncover large samples of fast (trise ≲ 5 d), luminous (Mpeak < -18), blue transients. While commonly attributed to the breakout of a supernova shock into a dense wind, the great distances to the transients of this class found so far have hampered detailed investigation of their properties. We present photometry and spectroscopy from a comprehensive worldwide campaign to observe AT 2018cow (ATLAS 18qqn), the first fast-luminous optical transient to be found in real time at lowredshift. Our first spectra (10 days. The spectrum remains extremely hot throughout its evolution, and the photospheric radius contracts with time (receding below R < 1014 cm after 1 month). This behaviour does not match that of any known supernova, although a relativistic jet within a fallback supernova could explain some of the observed features. Alternatively, the transient could originate from the disruption of a star by an intermediate-mass black hole, although thiswould require long-lasting emission of highly super-Eddington thermal radiation. In either case, AT 2018cow suggests that the population of fast luminous transients represents a new class of astrophysical event. Intensive follow-up of this event in its late phases, and of any future events found at comparable distance, will be essential to better constrain their origins.

Objective: To describe mid-term outcomes of the use of EndoAnchors as an adjunct for arch and thoracic endovascular aortic repair (TEVAR)., Methods: A retrospective multicentre series from nine centres using the Heli-FX EndoAnchor System (Medtronic Inc, Minneapolis, USA) at TEVAR over May 2014-May 2019 is presented. The study is registered at ClinicalTrials.gov with number NCT04100499. The primary outcome was freedom from Type I endoleak at EndoAnchors deployments; secondary outcomes included evaluation of aortic wall penetration (AWP) at first computed tomography scan, EndoAnchor-related issues and mortality., Results: 54 high-risk patients (35 males/19 females, age 73 ± 11 years) with arch, thoracic and thoracoabdominal aneurysmal disease (3 chronic post-dissection and one patch pseudoaneurysm), with a mean neck length 19.7 ± 6.6 mm that were treated with multiple hybrid and endovascular techniques were included. A total of 329 EndoAnchors were used with a mean of 6.1 ± 2.5 per patient. Overall adequate AWP was 86%, whereas arch (Ishimaru's zones 0-2) deployments achieved 80.6% when compared to 87.3% in descending thoracic aorta (dTA); although there was no statistical significance. Freedom from type I endoleaks was 88% at 2 year follow-up, due to 4 type IA endoleaks, two of them successfully treated, one with conservative treatment due to complexity of repair and remaining patient died 1 year later due to endograft infection. There were reported five EndoAnchor-related issues; four losses and one renal stent-graft was crushed due to catheter deflection solved with balloon reinflation. None of the losses had clinical significance. Overall mortality is described for 7 (9.5%) patients, one of them aneurysm-related., Conclusions: The adjunctive use of EndoAnchors in TEVAR and complex TEVAR procedures achieved acceptable outcomes at midterm in a high-risk series with hostile seal zones. Still, they should be still judiciously used as there is lack of data to suggest a more liberal use; therefore, the landing zone should not be compromised in favour of their use.

Background: Abdominal aortic aneurysm (AAA) is an important cardiovascular (CV)-related disease that requires surgical treatment to prevent rupture. The elevation of arterial stiffness (AS) is an increasingly recognized independent determinant of CV morbidity and mortality and plays a special role in atherosclerosis. The importance of the surgical technique used for AAA repair in the long-term outcomes still needs to be clarified, and whether endovascular aortic repair (EVAR) or open surgical repair (OSR) confers high AS measurements and thus worse prognosis in terms of CV morbidity needs further investigation., Methods: A prospective nonrandomized study that included consecutive patients requiring either EVAR or OSR for AAA disease between February 2015 and January 2016 was conducted. This study is registered on the National Institutes of Health website (ClinicalTrials.gov) and identified with NCT02642952. Several noninvasive measurements of AS and central aortic hemodynamics were obtained before surgery and in the first postoperative control (4-6 weeks), with change from baseline in heart rate-adjusted augmentation index (AIx@75) as main outcome. Likewise, inflammatory circulating biomarkers were also measured in the same time line., Results: We included 44 patients, 25 in the EVAR group and 19 in the OSR group. Subjects who underwent EVAR were older and presented larger aneurysm diameter at baseline. There was a significant decrease in AIx@75 in the EVAR group after treatment (-4.1 ± 8.1%, P = 0.018), for a moderate effect size (d = 0.508), whereas the decreasing trend in the OSR group (-2.5 ± 6.7%, P = 0.127) was not statistically significant. No significant changes in carotid-radial pulse wave velocity (PWV CR ) and central blood pressures were observed. The inflammatory markers increased after surgical repair, with significant changes in homocysteine in both EVAR (5.2 ± 6.9 μmol/L, P = 0.002) and OSR (1.8 ± 2.1 μmol/L, P = 0.002) groups., Conclusions: Our study suggests that both treatments confer better postoperative values of AS measured by AIx@75 and produces no changes in PWV CR , in the early term. Whether this situation is maintained during follow-up needs further investigation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Abstract: Peltogyne mexicana heartwood might be a novel purple pigment source. The results of the present study demonstrate that the purple pigment is an important source of phenolic compounds (698.22 ± 2.99 mg GAE/g) and flavonoids (48.01 ± 0.51 mg EPE/g). UV-Vis spectrum and color parameters ( L * a * b *) showed that purple pigment has different shades of purple-red ( H ° value 19.32 ± 0.02 in methanol and 22.85 ± 0.01 in ethanol) depending on the solvent and the pH. Also, the purple pigment did not exhibit acute oral toxicity at a single dose (2000 mg/kg body weight). No mutagenicity was observed in the Ames test with three Salmonella typhimurium strains. The purple pigment exhibited considerable coloring properties with a wider range of citric acid-dependent color hues in gelatin ( H ° from 280.3 to 319.9 and from 68.0 to 88.1), and higher color intensity than commercial anthocyanin. Minor variations in the hue were found in yogurt, for purple pigment with H ° values from 317.5 to 315.0, and commercial anthocyanin from 82.6 to 88.7 and 276.9 to 295.5. However, purple pigment required lower concentrations to achieve superior effects. For gelatin and yogurt samples, similar variations in the color parameters L *, a *, b *, and pigment degradation were observed for purple pigment and commercial anthocyanin in the stability assay.

We present subarcsecond 1.3 mm continuum ALMA observations towards the Orion Molecular Cloud 1 South (OMC-1S) region, down to a spatial resolution of 74 AU, which reveal a total of 31 continuum sources. We also present subarcsecond 7 mm continuum VLA observations of the same region, which allow to further study fragmentation down to a spatial resolution of 40 AU. By applying a Mean Surface Density of Companions method we find a characteristic spatial scale at ~ 560 AU, and we use this spatial scale to define the boundary of 19 'cores' in OMC-1S as groupings of millimeter sources. We find an additional characteristic spatial scale at ~ 2900 AU, which is the typical scale of the filaments in OMC-1S, suggesting a two-level fragmentation process. We measured the fragmentation level within each core and find a higher fragmentation towards the southern filament. In addition, the cores of the southern filament are also the densest (within 1100 AU) cores in OMC-1S. This is fully consistent with previous studies of fragmentation at spatial scales one order of magnitude larger, and suggests that fragmentation down to 40 AU seems to be governed by thermal Jeans processes in OMC-1S.

Aberrant right subclavian arteries occur in as much as 2% of the population. Aneurysms in this vessel are rare but exhibit a marked propensity toward rupture; therefore, early elective treatment is indicated. Transluminally placed stent-grafts offer an alternative approach to the standard surgical treatment. This type of procedure is less invasive, with less attendant risk than operative repair. Because there was no proximal neck between the aneurysm and Kommerell diverticulum in the case described herein, it was decided to perform endovascular exclusion of the aneurysm by inserting an endoprosthesis to occlude the aortic exit of the aneurysm, combined with distal ligation. A bilateral carotid/subclavian bypass was also created to preserve the function of both subclavian arteries.