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This study investigated Perkinsus spp. infecting Crassostrea rhizophorae from the Jaguaribe River estuary, Ceará, Brazil. Fragments of gills and rectum of the oysters (n=150) were incubated in Ray's fluid thioglycollate medium (RFTM). Genus Perkinsus-specific PerkITS85/750 PCR assays were performed and their amplicons were sequenced by the Sanger method. The RFTM assays confirmed Perkinsus spp. The sequencing of the amplified fragments from the rDNA internal transcribed spacers (ITS) of Perkinsus spp. confirmed Perkinsus chesapeaki. Neighbor-Joining analyzes place P. chesapeaki identified in this study in a well-supported clade with other isolates of the same species. This is the first record of P. chesapeaki infecting C. rhizophorae in South America.

This work investigated the occurrence of Perkinsus sp. in clam Anomalocardia brasiliana, oyster Crassostrea sp. and mussel Mytella falcata from the Jaguaribe River estuary, northeastern Brazil. The collection of clam (N = 300), oysters (N = 300) and mussels (N = 300) were carried out in the estuary of the Jaguaribe River, Ceará, in March and April (rainy season) and October (dry season) in 2017. The mollusks were measured in their major axis, open, and had their tissues submitted to tissue incubation techniques in Ray's fluid thioglycollate medium (RFTM), histology, real-time polymerase chain reaction (qPCR), PCR and sequencing. The RFTM assays showed Perkinsus sp. infecting the three mollusks investigated. The prevalence of infected clams was 1.33% in both sampling periods, oysters ranged from 2.66 (rainy season) to 8% (dry period), and mussels from 0% (dry period) to 51.33% (rainy season). The intensity of infection was very light to light in clams, very soft to severe in oysters and very soft to moderate in mussels. Histological analyses showed cells of Perkinsus sp. infecting the gills and connective tissue around the digestive gland of some individuals. The qPCR generated amplicons in all positive samples in RFTM, confirming the presence of Perkinsus sp., while the sequencing evidenced high similarity (99%) with the species P. beihaiensis. In conclusion, the results obtained contribute to increasing knowledge about the occurrence of Perkinsus sp. in bivalve mollusks from northeastern Brazil.

Abstract-In this experimental study the evolution of gas characteristics during the gasification of olive bagasse particles was investigated using a semi-batch fluidized-bed gasifier. Sand particles with a mean diameter of 375 μm were used as bed material and an air flow was used as the fluidizing agent. Experimental tests were conducted with particles of diameter ranging from in 1.25 to 2 mm. The material was characterised through elemental and proximate analysis, and the higher heating value was also measured. In each run, the major components of the gas phase were identified as CO, CO 2 , H 2 , CH 4 , O 2 and N 2 . Gaseous samples were collected and analysed by gas chromatography (Dani 1000 DPC). The effect of air/biomass ratio on gasification performance was studied. The tests were conducted at three different air flow rates and the load of biomass was also changed. The results show that the of air flow increases the H 2 , CO and CH 4 content in the producer gas. Results also show an increase in the dry gas yield, carbon conversion and the gas heating values as air flow rate decreases. Findings reveal as well that the increase of biomass load reduces the composition in H 2 CO and CH 4 of the producer gas, leading to the decrease of the gasification performance parameters.Index Terms-Gasification, olive bagasse particles, producer gas, semi-batch fluidized bed.