51 research outputs found
Preliminary results of a Exploratory Fishing targeting deep-water species off Uruguay
A Pilot Action of Exploratory Fishing was carried out in the second half of 2001 by two
Spanish bottom-longline commercial fishing vessels within the Uruguayan Economic
Exclusive Zone (EEZ) targeting deep-water species. Trap fishing gears were also
utilised as another alternative fishing gears.The main objective of the exploratory survey
was to improve the knowledge of the distribution and the population structure of the
species target of the survey: Groupers (Epinephelus spp.), Kingclip (Genypterus
blacodes), Brazilian sandperch (Pinguipes spp.) and other accompanying species.
Some preliminary results of this exploratory survey are shown in this current work.
Fishery and biological data were collected by scientific observers on board of the two
vessels which took part in the exploratory fishing. The collected data were date, time,
position, depth, SST, SBT, weather condition, catches, discards, length distributions,
sex, maturity, stomach fullness… among others. Length distributions, sex ratio and
maturity stage of the most abundant species in the catch are also shown.
Catch, effort and CPUE by area, gear and depth strata were analysed. Regarding bottom
longline gear, the most abundant species were Dogfish shark (Squalus sp), Wreckfish
(Polyprion americanus), Tope shark (Galeorhinus galeus) and Argentine hake
(Merluccius hubbsi) in waters shallower than 200 m depth. Regarding Traps fishing
gears, the most abundant species were crabs (Family Geryonidae) and Argentine conger
(Conger orbignyanus)
A new displacement-based approach to calculate stress intensity factors with the boundary element method
The analysis of cracked brittle mechanical components considering linear elastic fracture mechanics is usually reduced to the evaluation of stress intensity factors (SIFs). The SIF calculation can be carried out experimentally, theoretically or numerically. Each methodology has its own advantages but the use of numerical methods has be-come very popular. Several schemes for numerical SIF calculations have been developed, the J-integral method being one of the most widely used because of its energy-like formulation. Additionally, some variations of the J-integral method, such as displacement-based methods, are also becoming popular due to their simplicity. In this work, a simple displacement-based scheme is proposed to calculate SIFs, and its performance is compared with contour integrals. These schemes are all implemented with the Boundary Element Method (BEM) in order to exploit its advantages in crack growth modelling. Some simple examples are solved with the BEM and the calculated SIF values are compared against available solutions, showing good agreement between the different schemes
Debate sobre o artigo de Narvai et al.
English title: Debate on the paper by Narvai et al.Margareth Crisóstomo Portela & Mauricio Teixeira Leite de Vasconcello
Deep-sequencing reveals broad subtype-specific HCV resistance mutations associated with treatment failure
A percentage of hepatitis C virus (HCV)-infected patients fail direct acting antiviral (DAA)-based treatment regimens, often because of drug resistance-associated substitutions (RAS). The aim of this study was to characterize the resistance profile of a large cohort of patients failing DAA-based treatments, and investigate the relationship between HCV subtype and failure, as an aid to optimizing management of these patients. A new, standardized HCV-RAS testing protocol based on deep sequencing was designed and applied to 220 previously subtyped samples from patients failing DAA treatment, collected in 39 Spanish hospitals. The majority had received DAA-based interferon (IFN) a-free regimens; 79% had failed sofosbuvir-containing therapy. Genomic regions encoding the nonstructural protein (NS) 3, NS5A, and NS5B (DAA target regions) were analyzed using subtype-specific primers. Viral subtype distribution was as follows: genotype (G) 1, 62.7%; G3a, 21.4%; G4d, 12.3%; G2, 1.8%; and mixed infections 1.8%. Overall, 88.6% of patients carried at least 1 RAS, and 19% carried RAS at frequencies below 20% in the mutant spectrum. There were no differences in RAS selection between treatments with and without ribavirin. Regardless of the treatment received, each HCV subtype showed specific types of RAS. Of note, no RAS were detected in the target proteins of 18.6% of patients failing treatment, and 30.4% of patients had RAS in proteins that were not targets of the inhibitors they received. HCV patients failing DAA therapy showed a high diversity of RAS. Ribavirin use did not influence the type or number of RAS at failure. The subtype-specific pattern of RAS emergence underscores the importance of accurate HCV subtyping. The frequency of “extra-target” RAS suggests the need for RAS screening in all three DAA target regions
- …