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1.
Rev. biol. trop ; 72(supl.1): e58623, Mar. 2024. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1559338

RESUMO

Abstract Introduction: The sea cucumber Holothuria (Halodeima) grisea Selenka, 1867 is a common echinoderm in intertidal regions along the Brazilian coast, which recently became the focus of unreported and unregulated fisheries. This study was carried out in sandy-rocky substrates at Armação do Itapocoroy, Penha, Santa Catarina (26o47' S; 48o36' W), near its southern limit of geographic distribution. Objective: To determine the densities (individuals*m-2) of Holothuria (H.) grisea within a spatial-temporal perspective as well as to determine biometric and growth characteristics of the population. Methods: Two-meter wide transects perpendicular to the coastline were carried out in winter and spring 2019 and in summer and spring 2020, in periods of spring low-tides. In each sampling occasion the total number of specimens of H. grisea were determined, and a group of 90 organisms was submitted to in situ biometrics (weight, length and width), and immediately returned alive to their habitat. Results: The densities of H. (H.) grisea were significantly higher in the subtidal sector and lower in the upper intertidal sector with no indication of significant differences among sampling campaigns. Depth was the primary factor explaining the observed density patterns and rugosity of the substrate was secondary but also important. The body length ranged from 5.2 to 22.5 cm, whereas the weight varied from 6.0 to 230 g. The mean and modal lengths were 12.54 and 13 cm, respectively. Approximately 75 % of the population sampled was between 10 and 14 cm and the average weight was 60 g. Estimates from von Bertalanffy growth function indicate that the youngest sea cucumber was one year-old, and the oldest had approximately two and a half years. Conclusions: This is the first study to determine biometric parameters for H. (H.) grisea in southern Brazil and the first one to estimate growth and age estimates for a wild population of this species. The densities recorded in the present study were lower than those previously reported for this region, suggesting anthropic influence.


Resumen Introducción: El pepino de mar Holothuria (Halodeima) grisea Selenka, 1867 es un equinodermo común en las regiones intermareales a lo largo de la costa brasileña, que recientemente se convirtió en foco de pesquerías no declaradas y no reguladas. Este estudio se realizó en sustratos arenosos-rocosos en Armação do Itapocoroy, Penha, Santa Catarina (26o47' S; 48o36' W), cerca del límite sur de su distribución geográfica. Objetivo: Determinar las densidades (individuos*m-2) de Holothuria (H.) grisea dentro de una perspectiva espacio-temporal así como determinar las características biométricas y de crecimiento de la población. Métodos: Se realizaron transectos de dos metros de ancho perpendiculares a la línea de costa en invierno y primavera de 2019 y en verano y primavera de 2020, en periodos de bajamar sicigia. En cada ocasión de muestreo se determinó el número total de especímenes de H. (H.) grisea, y se sometió un grupo de 90 organismos a biometría in situ (peso, longitud y ancho), e inmediatamente se los devolvieron vivos a su hábitat. Resultados: Las densidades de H. (H.) grisea fueron significativamente más altas en el sector submareal y más bajas en el sector intermareal superior sin indicios de diferencias significativas entre las campañas de muestreo. La profundidad fue el factor principal que explica los patrones de densidad observados y la rugosidad del sustrato fue secundaria pero también importante. La longitud del cuerpo varió de 5.2 a 22.5 cm, mientras que el peso varió de 6.0 a 230 g. Las longitudes media y modal fueron 12.54 y 13 cm, respectivamente. Aproximadamente el 75 % de la población muestreada midió entre 10 y 14 cm y el peso promedio fue de 60 g. Estimados de la función de crecimiento de von Bertalanffy indican que el ejemplar más joven presentaba un año de edad, mientras el más viejo presentaba cerca de dos años y medio. Conclusiones: Este es el primer estudio que determina parámetros biométricos para una población de H. (H.) grisea en el sur de Brasil y el primero en estimar el crecimiento y edades para una población salvaje de esta especie. Las densidades registradas en el presente estudio fueron inferiores a las reportadas previamente para esta región sugiriendo la ocurrencia de influencia antrópica.


Assuntos
Animais , Dinâmica Populacional , Holothuria/crescimento & desenvolvimento , Estudos de Amostragem
2.
Mar Environ Res ; 197: 106457, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38519355

RESUMO

Recent estimates of the size at first maturity (L50) of Sardinella brasiliensis showed contradictory results with a decreasing in the fish stock biomass encompassed by increasing values of L50. The methodological approach used hereby allowed to separate sardines classified in the virginal maturity stage from those categorized in the recovery stage, and ready for one next spawning event. This study evaluated the hypothesis of the existence of separated stocks experiencing distinct environmental conditions and fishing pressures which may have altered L50 estimates using a robust dataset based on biological samples collected along the entire species distribution area in the southeast-south Brazilian coast [Rio de Janeiro (RJ), São Paulo (SP), Paraná (PR), Santa Catarina (SC) and Rio Grande do Sul (RS)] between 2000 and 2018. A reclassification of the gonadal maturity stages provided a more realistic estimate of L50. Combining biological, reproductive, fishing data and the mean temperature of the catch (MTC), the leave-one-out classification correctly re-assigned individuals with an overall accuracy of 85% [100% (RJ), 45% (SP), 99% (PR), 99% (SC) and 82% (RS)]. The connectivity between the local populations of S. brasiliensis off RJ (23°S) and the southern populations is limited, contrasting to spatial structured semi-discrete population-units found between SP and RS (24°S-30°S). The northern extreme population-unit (RJ, 22°S-23°S) showed an expressive reduction of L50, and a negative correlation was detected between the increasing MTC values and the abundance of early maturing individuals and recruits of the species. Stock specific L50 estimates seemed to act as indicators of long term environmental fluctuations.


Assuntos
Pesqueiros , Reprodução , Animais , Brasil , Gônadas , Peixes , Oceano Atlântico
3.
Biology (Basel) ; 13(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38248448

RESUMO

The study of geometric morphometrics among stocks has proven to be a valuable tool in delineating fish spatial distributions and discriminating distinct population units. Variations in fish body morphology can be linked to genetic factors or to phenotypic adaptability in response to environmental variables. The tub gurnard (Chelidonichthys lucerna) is a demersal species that usually lives in the bottom of the continental shelf, being widely distributed along the northeast Atlantic, Mediterranean and Black seas. Worldwide interest in the species has increased since 2006, when ICES recognized its potential for commercial exploitation. However, despite its broad geographic occurrence, to date, research on C. lucerna population structure at large spatial scales is still lacking. In this paper, body geometric morphometrics, using a landmark-based truss network, was applied in order to discriminate C. lucerna populations caught in three different fishery grounds areas along the northeast Atlantic: Conwy Bay (United Kingdom), Biscay Bay (Spain) and Matosinhos (Portugal). The results obtained in this study revealed a high overall relocation success (95%) of samples to their original locations, thus demonstrating the existence of significant regional differences and indicating that we are dealing with different fish population units. Moreover, the data revealed a partial overlap between individuals from Spain and United Kingdom, suggesting that in geographically distant areas these populations may inhabit similar environments. However, to corroborate these findings, future works using a holistic approach with alternative and complimentary stock assessment tools (e.g., genetic and phenotypic natural tags) are highly recommended.

4.
Biology (Basel) ; 11(7)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-36101386

RESUMO

In this study, otolith geochemical signatures (Element:Ca ratios) were used to investigate the long-term spatial shifts of the population structure of Isopisthus parvipinnis, Bigtooth corvina, an economically and ecologically important Brazilian fish species. Two-hundred and ninety-seven juvenile individuals from historical (1975) and contemporary (2018/2019) samples were collected in five subareas [São Paulo: North-NSP, Center-CSP and South-SSP; Paraná (PR) and Santa Catarina (SC)] of the shallow waters off the coast of the South Brazil Bight were analyzed. The main informative single elements were Co:Ca, Cu:Ca, Li:Ca, Mg:Ca, Mn:Ca, Ni:Ca, Na:Ca, and Rb:Ca. Multivariate analysis showed spatial differences in otolith chemical composition over the years. Samples from 1975 presented an overall low reclassification rate (58%), suggesting the existence of two population units: (1) SP + PR; and (2) SC. However, samples from 2018/2019 discriminated four distinct population units with a good overall reclassification (80%): (1) NSP; (2) CSP; (3) SSP + PR; and (4) SC. This spatial differentiation on the geochemical signatures probably reflects the effects of long-term temporal variability in oceanographic conditions, anthropogenic influence, and climate change on this coastal ecosystem. The data also corroborate and refines the population structure scenario of I. parvipinnis recently described using complementary phenotypic tags.

5.
Psicol. argum ; 39(106): 950-984, jul.-set. 2021. tab
Artigo em Português | Index Psicologia - Periódicos | ID: psi-72436

RESUMO

O presente trabalho parte de uma pesquisa sobre nascimento dos poderes disciplinares e das sanções privativas de liberdade no período moderno a partir de Foucault, acompanhando as transformações e os efeitos de tais poderes no decorrer da história até o período pós-moderno, com base em Agamben e Bauman. Tais poderes parecem ter como objetivo uma correção dos sujeitos, contudo, nas sociedades modernas, apresentam seu caráter excludente através da criação da figura do delinquente. Com avanço à pós-modernidade, as tecnologias de exclusão são aprimoradas, dando finalidades mercantis e úteis às novas políticas dos Estados por meio da normalização de profundas violações de direitos fundamentais, alcançando até o mesmo direito de ser humano, ou cidadão, conforme Agamben explica na figura do Homo sacer. Por fim, analisamos como tais poderes tem influenciado políticas e uma rápida expansão do Direito penal, tendendo a transferir as repostas da seguridade social à biopolítica nascida da sistemática carcerária.(AU)


The present work derives from a research on the birth of the disciplinary powers and the custodial sanctions in the modern period from Foucault on, accompanying the transformations and effects of such powers throughout history until the postmodern period, based in Agamben and Bauman. Such powers seem to be aimed at correcting the subjects, however, in modern societies, they present its exclusionary character through the creation of the figure of the offender. With advancement to post-modernity, exclusion Technologies are improved, giving mercantile and useful purposes to the new policies of the States through the normalization of profound violations of fundamental rights, reaching even the right to be human, or citizen, as Agamben explains in the figure of Homo sacer. Lastly, we analyze how such powers have influenced policies and a rapid expansion of the Criminal law, tending to transfer the answers from social security to biopolitics born from the prison system.(AU)


Assuntos
Humanos , Masculino , Feminino , Direito Penal , Prisões , Política Pública , Sanção , Violação de Direitos Humanos , Psicologia Social
6.
Neurosci Lett ; 512(1): 43-7, 2012 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-22326387

RESUMO

INTRODUCTION: Growing evidence suggests that oxidative stress (OS) may be associated with the pathophysiology underlying schizophrenia (SZ). Some studies indicate that nutritional supplements offer protection from OS, but there is no data about the effect of a hypocaloric diet on OS in this population. Therefore, we aimed to study the effect of a hypocaloric dietary intervention on OS in subjects with SZ. METHODS: A cross-sectional study of 96 participants in outpatient treatment for SZ comprised patients separated into two groups: one group of subjects followed a hypocaloric diet (HD) program (n=42), while the other group followed a regular diet (RD) with no nutritional restrictions (n=54). The serum total radical-trapping antioxidant parameter (TRAP), total antioxidant reactivity (TAR) and thiobarbituric acid reactive species (TBARS) levels were assessed. RESULTS: TRAP levels were lower and TBARS levels were higher in the HD group than in the RD group (p=0.022 and p=0.023, respectively). There were no differences in TAR levels between the groups. Additionally, there was a positive correlation between TRAP and TBARS levels after adjusting for BMI and clozapine dose (partial correlation=0.42, p<0.001). There were no correlations among the length of illness or diet and the levels of TRAP, TBARS, and TAR. CONCLUSIONS: Subjects with SZ on a hypocaloric diet displayed different OS parameters than those not following a HD. Serum TRAP levels were lower and TBARS levels were higher among SZ subjects with HD compared to SZ subjects without HD. Lower TRAP levels may reflect decreased oxidative stress, whereas higher TBARS levels most likely reflect a biochemical reaction to the decreased TRAP levels. Additionally, TAR levels were similar between groups, suggesting a similar quality of antioxidant defenses, despite quantitative differences between the two dietary protocols in SZ patients under outpatient care.


Assuntos
Antioxidantes/análise , Restrição Calórica , Peroxidação de Lipídeos , Estresse Oxidativo , Esquizofrenia/dietoterapia , Estudos Transversais , Feminino , Humanos , Masculino , Esquizofrenia/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Adulto Jovem
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