Browsing by Author "Matos, Ana"
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- Aerobic and anoxic growth and nitrate removal capacity of a marine denitrifying bacterium isolated from a recirculation aquaculture systemPublication . Borges, Maria-Teresa; Sousa, André; Marco, Paolo De; Matos, Ana; Hönigova, Petra; Castro, Paula M. L.Bacterial biofilters used in marine recirculation aquaculture systems need improvements to enhance nitrogen removal efficiency. Relatively little is known about biofilter autochthonous population structure and function. The present study was aimed at isolating and characterizing an Autochthonous denitrifying bacterium from a marine biofilter installed at a recirculation aquaculture system. Colonization of four different media in a marine fish farm was followed by isolation of various denitrifying strains and molecular classification of the most promising one, strain T2, as a novel member of the Pseudomonas fluorescens cluster. This strain exhibits high metabolic versatility regarding N and C source utilization and environmental conditions for growth. It removed nitrate through aerobic assimilatory metabolism at a specific rate of 116.2 mg NO3-N g dw _1 h _1. Dissimilatory NO3-N removal was observed under oxic conditions at a limited rate, where transient NO2-N formed represented 22% (0.17 mg L _1) of the maximum transient NO2-N observed under anoxic conditions. Dissimilatory NO3-N removal under anoxic conditions occurred at a specific rate of 53.5 mgNO3-N g dw _1 h _1. The isolated denitrifying strain was able to colonize different materials, such as granular activated carbon (GAC), Filtralite and Bioflow plastic rings, which allow the development of a prototype bioreactor for strain characterization under dynamic conditions and mimicking fish-farm operating conditions.
- Microbial monitoring of a subsurface constructed wetland treating domestic wastewaterPublication . Mina, Isabel A-P.; Costa, Marta; Matos, Ana; Calheiros, Cristina S.C.; Castro, Paula M. L.
- A molecular and multivariate approach to the microbial community of a commercial shallow raceway marine recirculation system operating with a moving bed biofilterPublication . Matos, Ana; Borges, Maria-Teresa; Peixe, Carla; Henriques, Isabel; Pereira, Carlos M.; Castro, Paula M. L.Information on commercial aquaculture systems bacterial communities is scarce. The present study was performed in a turbot shallow raceway recirculating aquaculture system throughout 221 days after initial fish stocking. The dynamics of bacteria attached to a Moving Bed Biofilm Reactor and the distribution of the system culturable planktonic heterotrophic bacteria were assessed. Different levels of free heterotrophic bacteria were found over time: <= 2.6 x 10(4) CFU mL(-1) in incoming and ozonated water and >= 1.5 x 10(6) CFU mL(-1) in raceway and biofilter water. 16S rRNA gene sequencing of nine strains persistently isolated from the system affiliated with Bacteroidetes, alpha-Proteobacteria or gamma-Proteobacteria. Polymerase chain reaction-denaturating gradient gel electrophoresis (PCR-DGGE) data showed temporal and spatial segregation of attached biofilter community. The first 32 days were the most important for bacterial establishment with higher culturable bacteria biomass loadings and higher community diversity. Multivariate canonical correspondence analysis of PCR-DGGE showed that the most common aquaculture water quality descriptors explained 70% of the DGGE pattern variability.
- Psychometric properties of the dimensional Yale Food Addiction Scale for Children 2.0 among portuguese adolescentsPublication . Matos, Ana; Félix, Sílvia; Coelho, Carol; Conceição, Eva; Machado, Bárbara César; Gonçalves, SóniaThe dimensional Yale Food Addiction Scale for Children 2.0 (dYFAS-C 2.0) was developed to provide a reliable psychometric measure for assessing food addiction in adolescents, in accordance with the updated addiction criteria proposed in the fifth edition of the Diagnostic and Statistical Manual (DSM-5). The present study aimed to evaluate the psychometric properties of the dYFAS-C 2.0 among Portuguese adolescents and pre-adolescents and to explore the relationship between food addiction and other eating behaviors such as grazing and intuitive eating. The participants were 131 Portuguese adolescents and pre-adolescents (53.4% female and 46.6% male) aged between 10 and 15 years (Mage = 11.8) and with a BMI between 11.3 and 35.3 (MBMI z-score = 0.42). Confirmatory Factor Analysis demonstrated an adequate fit for the original one-factor model (χ2 (104) = 182; p < 0.001; CFI = 0.97; TLI = 0.97; NFI = 0.94; SRMR = 0.101; RMSEA = 0.074; 95% CI [0.056; 0.091]). Food addiction was positively correlated with higher grazing (r = 0.69, p < 0.001) and negatively correlated with lower reliance on hunger/satiety cues (r = −0.22, p = 0.015). No significant association was found between food addiction and BMI z-score, or between food addiction and age. The results support the use of dYFAS-C 2.0 as a valid and reliable measure for assessing food addiction in Portuguese adolescents and pre-adolescents. Furthermore, the findings highlight that food addiction may be part of a spectrum of disordered eating behaviors associated with control impairment. Future research with a larger sample size could further elucidate the associations between food addiction and other variables, such as psychological distress and multi-impulsive spectrum behaviors.