Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Remineralization of particulate organic carbon in an ocean oxygen minimum zone

This work was funded by a NERC standard grant NE/E01559X/1

Overlapping pK a of the Multiprotic Hemostyptic Eltrombopag using UV–Vis Multiwavelength Spectroscopy and Potentiometry

pH-potentiometric and WApH-spectrophotometric titrations of the multiprotic hemostyptic Eltrombopag for dissociation constants determination were compared. Hemostyptic and hemostatic Eltrombopag treats low blood platelet counts in adults with chronic immune idiopathic thrombocytopenia ITP. Eltrombopag exhibits five protonatable sites in a pH range of 2 to 10, where only two pK are well separated (ΔpK > 3), while the other three are near dissociation constants of overlapping equilibria. According to MARVIN prediction, in the neutral medium Eltrombopag occurs in the slightly water soluble form LH3 that can be protonated to the soluble species LH4 and LH5 The molecule LH3 can be dissociated to still difficultly soluble species LH2, LH and L. Due to limited solubility of Eltrombopag above pH 9.5 the protonation was studied up to pH 10. Five dissociation constants can be reliably determined with REACTLAB and SQUAD84 leading to the same value. From a dependence on ionic strength the thermodynamic dissociation constants were estimated at 25°C: pKa1T = 2.69, pKa2T = 6.97, pKa3T = 7.13, pKa4T = 7.65, pKa5T = 8.30. Since pH above 10 and pH down 5 occurs in a titrated solution the very fine precipitate of Eltrombopag which is initially forming a slight opalescence, this part of the potentiometric titration curve pH over 9 and pH below 5 was not taken into regression analysis to estimate pKa2 = 6.53(01), pKa3 = 7.60(04), pKa4 = 9.62(59), pKa5 = 10.55(340) at 25°C with ESAB and HYPERQUAD.Byly porovnávány potenciometrické hodnoty pH a WApH spektrofotometrické titrace multiprotického hemostyptického Eltrombopagu pro stanovení disociačních konstant. Hemostyptický a hemostatický Eltrombopag léčí nízké počty krevních destiček u dospělých pacientů s chronickou imunitní idiopatickou trombocytopenií ITP. Eltrombopag vykazuje pět protonovatelných míst v rozmezí pH od 2 do 10, kde jsou jen dva pK dobře oddělené (ΔpK> 3), zatímco ostatní tři jsou téměř disociační konstanty překrývající se rovnováhy. Podle predikce společnosti MARVIN se v neutrálním prostředí Eltrombopag vyskytuje ve formě lehce rozpustné ve vodě LH3, která může být protonována na rozpustné druhy LH4 a LH5. Molekula LH3 může být disociována na stále obtížně rozpustné druhy LH2, LH a L. Vzhledem k omezenému rozpustnosti Eltrombopagu nad pH 9,5 byla zkoumána protonace až na pH 10. Pět disociačních konstant může být spolehlivě stanoveno pomocí REACTLAB a SQUAD84, což vede k stejné hodnotě. Ze závislosti na iontové síle byly termodynamické disociační konstanty odhadnuty na 25 ° C: pKa1T = 2,69, pKa2T = 6,97, pKa3T = 7,13, pKa4T = 7,65, pKa5T = 8,30. Vzhledem k tomu, že pH v hodnotě nad 10 a pH 5 se vyskytuje v titrovaném roztoku, velmi jemná sraženina Eltrombopagu, která zpočátku vytváří mírnou opalescenci, tato část potenciometrické titrační křivky pH nad 9 a pH pod 5 nebyla převzata do regresní analýzy k odhadu pKa2 = 6,53 (01), pKa3 = 7,60 (04), pKa4 = 9,62 (59), pKa5 = 10,55 (340) při 25 ° C pomocí ESAB a HYPERQUAD

Altered neocortical dynamics in a mouse model of Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a rare neurodevelopmental disorder characterized by moderate intellectual disability and learning difficulties alongside behavioral abnormalities such as hypersociability. Several structural and functional brain alterations are characteristic of this syndrome, as well as disturbed sleep and sleeping patterns. However, the detailed physiological mechanisms underlying WBS are mostly unknown. Here, we characterized the cortical dynamics in a mouse model of WBS previously reported to replicate most of the behavioral alterations described in humans. We recorded the laminar local field potential generated in the frontal cortex during deep anesthesia and characterized the properties of the emergent slow oscillation activity. Moreover, we performed micro-electrocorticogram recordings using multielectrode arrays covering the cortical surface of one hemisphere. We found significant differences between the cortical emergent activity and functional connectivity between wild-type mice and WBS model mice. Slow oscillations displayed Up states with diminished firing rate and lower high-frequency content in the gamma range. Lower firing rates were also recorded in the awake WBS animals while performing a marble burying task and could be associated with the decreased spine density and thus synaptic connectivity in this cortical area. We also found an overall increase in functional connectivity between brain areas, reflected in lower clustering and abnormally high integration, especially in the gamma range. These results expand previous findings in humans, suggesting that the cognitive deficits characterizing WBS might be associated with reduced excitability, plus an imbalance in the capacity to functionally integrate and segregate information.This work was supported by EU H2020 Research and Innovation Programme under Grant Agreement No. 720270 (HBP SGA2), BFU2017-85048-R Spanish Ministry of Science and CERCA Programme/Generalitat de Catalunya to MVSV