Report of the ICCAT GBYP international workshop on Atlantic bluefin tuna growth

In the last Atlantic bluefin tuna assessment, an age-length database coming from direct ageing was presented for the first time. It was observed that otolith age estimates for fish younger than 8 years old had a smaller size at age compared to spine (first dorsal fin radius) age estimates. This difference, although small, was enough to misallocate the year class. This misallocation was solved when introducing a vector of bias corrected aged otoliths based on paired otolithspine samples. We have identified two possible causes for over-estimating age in the otolith agelength data: the current age adjustment criterion (to convert the bands counting into ages) and a reading bias in age estimations from some laboratories. Otolith preparation and reading protocols have been reviewed. The edge type and marginal increment analysis showed that the formation of opaque zones would seem likely to occur primarily between December through to June, contrary to what was thought until now, for which a new criterion for age adjustment has been proposed

Evolution of the use of corticosteroids for the treatment of hospitalised COVID-19 patients in Spain between March and November 2020: SEMI-COVID national registry

Objectives: Since the results of the RECOVERY trial, WHO recommendations about the use of corticosteroids (CTs) in COVID-19 have changed. The aim of the study is to analyse the evolutive use of CTs in Spain during the pandemic to assess the potential influence of new recommendations. Material and methods: A retrospective, descriptive, and observational study was conducted on adults hospitalised due to COVID-19 in Spain who were included in the SEMI-COVID- 19 Registry from March to November 2020. Results: CTs were used in 6053 (36.21%) of the included patients. The patients were older (mean (SD)) (69.6 (14.6) vs. 66.0 (16.8) years; p < 0.001), with hypertension (57.0% vs. 47.7%; p < 0.001), obesity (26.4% vs. 19.3%; p < 0.0001), and multimorbidity prevalence (20.6% vs. 16.1%; p < 0.001). These patients had higher values (mean (95% CI)) of C-reactive protein (CRP) (86 (32.7-160) vs. 49.3 (16-109) mg/dL; p < 0.001), ferritin (791 (393-1534) vs. 470 (236- 996) µg/dL; p < 0.001), D dimer (750 (430-1400) vs. 617 (345-1180) µg/dL; p < 0.001), and lower Sp02/Fi02 (266 (91.1) vs. 301 (101); p < 0.001). Since June 2020, there was an increment in the use of CTs (March vs. September; p < 0.001). Overall, 20% did not receive steroids, and 40% received less than 200 mg accumulated prednisone equivalent dose (APED). Severe patients are treated with higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%. Conclusions: Patients with greater comorbidity, severity, and inflammatory markers were those treated with CTs. In severe patients, there is a trend towards the use of higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%

Albacore (Thunnus Alalunga) stock structure in the Mediterranean sea

A review of genetic information and mark recapture data relevant to albacore stock structure in the Mediterranean Sea is summarized. Considering the genetic studies based on the albacore populations from the Atlantic Ocean and Mediterranean Sea, the albacore population in the Mediterranean constitutes a genetically differentiated stock separated by the strait of Gibraltar. The mark and recaptured data available in the ICCAT database are scarce and evenly distributed among years and areas. Most of the tag activity took place in the western Mediterranean area on discrete experiments. Nevertheless, the 38 recaptures obtained with information on location show most of the tagged albacore were recaptured in the Mediterranean Sea (95%) with only two specimens being recaptured in Atlantic waters (5%). Therefore, according to this information, the SCRS concluded that in order to assess the Mediterranean albacore population, it should be considered a separate stock from those in the Atlantic Ocean. Further studies, including more genetic analyses and electronic tagging, are required in order to confirm this hypothesis of a separate Mediterranean stock from the Atlantic Ocean stocks, as well as only one single stock within the Mediterranean Sea

A review of Mediterranean albacore (Thunnus alalunga) biology and growth studies

Growth parameters are used to estimate catch-at-age data which is required as an input to many stock assessment models. In the case of Mediterranean albacore stock no assessment has ever done (ICCAT, 2009). This study presents growth information based on spine section interpretation of annual time marks. A preliminary age-length key is presented for males, females and two sexes combined, based on 249 albacore (Thunnus alalunga, Bonn.1788) spine samples caught around the Balearic Islands and Western Mediterranean sea between June and November from 2004 thru 2006. The albacore length ranged from 52 cm to 94 cm for females and from 53 cm to 96 cm for males. Available length-weight data for 138 males and 162 females was analysed separately. New estimates presented in this study were compared with assumed biological length-weight relationship for Mediterranean albacore stock. As well, mean length by age estimates derived from the age-length-key obtained by reading fin ray section were compared with other studies that used hard parts to age Mediterranean albacore

Albacore (Thunnus Alalunga) stock structure in the Mediterranean sea

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A review od Mediterranean albacore (Thunnus alalunga) biology and growth studies

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A NuSTAR view of SS433: Precessional evolution of the jet-disk system

SS433 is a Galactic microquasar with powerful outflows (double jet, accretion disk and winds) with well known orbital, precessional and nutational period. In this work we characterise different outflow parameters throughout the precessional cycle of the system. We analyse 10 NuSTAR ($3-70$ keV) observations of $\sim$30~ks that span $\sim$1.5 precessional cycles. We extract averaged spectra and model them using a combination of a double thermal jet model (bjet) and pure neutral and relativistic reflection (xillverCp and relxilllpCp) over an accretion disk. We find an average jet bulk velocity of $\beta = v/c \sim0.29$ with an opening angle of $\lesssim$6~degrees. Eastern jet kinetic power ranges from 1 to $10^{39}$~erg/s, with base "coronal" temperatures $T_o$ ranging between 14 and 18 keV. Nickel to iron abundances remain constant at $\sim$9 (within 1$\sigma$). The western to eastern jet flux ratio becomes $\sim1$ on intermediate phases, about 35% of the total precessional orbit. The $3-70$ keV total unabsorbed luminosity of the jet and disk ranges from 2 to 20 $\times$10$^{37}$~erg/s, with the disk reflection component contributing mainly to the hard $20-30$ keV excess and the stationary 6.7 keV ionized Fe line complex. At low opening angles $\Theta$ we find that the jet expands sideways following an adiabatic expansion of a gas with temperature $T_o$. Finally, the central source and lower parts of the jet could be hidden by an optically thick region of $\tau > 0.1$ and size $R\sim N_H/n_{e0}\sim1.5\times10^9$~cm$\sim$1700~$r_g$ for $M_{BH}=3~M_{\odot}