102 research outputs found
Catches in ghost-fishing octopus and fish traps in the northeastern Atlantic Ocean (Algarve, Portugal)
Ghost fishing is the term used to describe the continued capture of fish and other living organisms after a
fisherman has lost all control over the gear. Traps may be lost for a variety of reasons including theft, vandalism,
abandonment, interactions with other gear, fouling on the bottom (i.e., traps and ropes are caught on rocky substrate), bad weather, and human error (Laist, 1995). Annual trap loss can be as high as 20% to 50% of fished traps in some fisheries (Al-Masroori et al., 2004). Because lost traps can continue to fish for long periods, albeit
with decreasing efficiency over time (e.g., Smolowitz, 1978; Breen, 1987, 1990; Guillory, 1993), ghost fishing is
a concern in fisheries worldwide
Catch composition, catch rates and size selectivity of three long-line methods in the Algarve (southern Portugal)
Three long-line methods have been studied in the Algarve: 1) small-hook long-line for inshore (less than 30 m) ‘white’ sea breams (Sparidae); 2) small-hook long-line for deeper water (40-60 m) ‘red’ sea breams; and 3) deep water (500-700 m) semi-pelagic long-line for hake Merluccius merluccius
(Linnaeus, 1758). Selectivity studies were carried out with three hook sizes in the first two cases: Mustad round-bent Quality 2369 hooks, numbers 15, 13, and 11, baited with a standardsized razor-shell Ensis siliqua (Linnaeus, 1758). Four hook sizes (numbers 10, 9, 7, and 5) of Stell round-bent, eyed hooks were used in the semi-pelagic long-line selectivity study, baited with a half of a standard-sized sardine. Some factors affecting catch composition and catch rates of the small
hook long-lines were also evaluated: bait, gangion length, setting time, fishing ground, and depth. Species diversity was relatively high, with 40, 36 and 27 species, respectively, in the three studies. However, the catches were dominated by a limited number of species. Catch rates (number
of fish per 100 hooks) were variable ( 20 %), with a general decrease in catch rate with increasing hook size in all the studies. In general, the catch size distributions for the different hook sizes for each species were highly overlapping, with little or no evidence of differences in
size selectivity. Hooks caught a wide size-range for each species, with few or no illegal-sized fish, in most cases. Some implications of these results for the management of multi-species, multi-gear fisheries are discussed.info:eu-repo/semantics/publishedVersio
Catch composition, catch rates and size selectivity of three long-line methods in the Algarve (southern Portugal)
Three long-line methods have been studied in the Algarve: 1) small-hook long-line for inshore (less than 30 m) ‘white' sea breams (Sparidae); 2) small-hook long-line for deeper water (40-60 m) ‘red' sea breams; and 3) deep water (500-700 m) semi-pelagic long-line for hake Merluccius merluccius (Linnaeus, 1758). Selectivity studies were carried out with three hook sizes in the first two cases: Mustad round-bent Quality 2369 hooks, numbers 15, 13, and 11, baited with a standardsized razor-shell Ensis siliqua (Linnaeus, 1758). Four hook sizes (numbers 10, 9, 7, and 5) of Stell round-bent, eyed hooks were used in the semi-pelagic long-line selectivity study, baited with a half of a standard-sized sardine. Some factors affecting catch composition and catch rates of the small hook long-lines were also evaluated: bait, gangion length, setting time, fishing ground, and depth. Species diversity was relatively high, with 40, 36 and 27 species, respectively, in the three studies. However, the catches were dominated by a limited number of species. Catch rates (number of fish per 100 hooks) were variable ( 5 %; 20 %), with a general decrease in catch rate with increasing hook size in all the studies. In general, the catch size distributions for the different hook sizes for each species were highly overlapping, with little or no evidence of differences in size selectivity. Hooks caught a wide size-range for each species, with few or no illegal-sized fish, in most cases. Some implications of these results for the management of multi-species, multi-gear fisheries are discussed.Tres artes de palangre han sido estudiados en Algarve: 1) palangre de anzuelo pequeño para espáridos de aguas costeras (menos de 30 m); 2) palangre de anzuelo pequeño para espáridos rojos de aguas mas profundas (40-60 m); y 3) palangre semipelágico de profundidad para merluza Merluccius merluccius (Linnaeus, 1758). En los dos primeros casos, los estudios de selectividad han utilizado anzuelos de tres tamaños: round bent marca Mustad modelo 2369 (números 15, 13 y 11), utilizando como cebo pedazos de navajas Ensis siliqua (Linnaeus, 1758) de la misma talla. En el estudio de selectividad con el palangre semipelágico se han utilizado cuatro tamaños de anzuelo (números 10, 9, 7 y 5) round hook de la marca Stell, con media sardina como cebo. Se evalúan, también, otros factores que afectan a la composición y a la tasa de captura de los palangres equipados con anzuelo pequeño: cebo, longitud de la puntera, hora de largada del aparejo, área de pesca y profundidad. La diversidad de especies en los tres estudios ha sido relativamente elevada: 40, 36 y 27 especies, respectivamente. Sin embargo, las capturas han sido dominadas por un número reducido de especies. Las tasas de captura (número de peces por 100 anzuelos) han variado ( 5 %; 20 %), observándose en los tres estudios un descenso general de las tasas de captura con el aumento del tamaño del anzuelo. De forma general, se ha observado una fuerte sobreposición de las distribuciones de las capturas con los diferentes tamaños de anzuelo para cada especie, con poca o ninguna evidencia de diferencias en la selectividad por talla. Los tamaños de anzuelo probados han capturado un rango de tallas amplio para cada especie, con escasa o ninguna captura de peces de talla ilegal en la mayorÃa de los casos. Se discuten algunas implicaciones de estos resultados en la gestión de pesquerÃas incluyendo varias especies y varios artes de pesca.Instituto Español de OceanografÃ
Impact of Carvedilol on the Mitochondrial Damage Induced by Hypoxanthine and Xantine Oxidase - What Role in Myocardial Ischemia and Reperfusion?
Objectivo: Os efeitos cardioprotectores do
carvedilol (CV) poderão ser explicados, em
parte, por interacções ao nÃvel da
mitocôndria cardÃaca. O objectivo deste
trabalho visou o estudo do efeito protector do
CV em mitocôndrias cardÃacas durante danos
oxidativos induzidos por hipoxantina e
xantina oxidase (HX/XO), uma conhecida
fonte de estresse oxidativo no sistema
cardiovascular.
Métodos: As mitocôndrias foram isoladas a
partir de corações de ratos Wistar (n=8) e
incubadas com o par HX/XO, na presença e
na ausência de cálcio. Vários métodos foram
utilizados de modo a verificar a acção
protectora do CV: avaliação das alterações de
volume mitocondrial (variação da densidade
óptica da suspensão mitocondrial), tomada e
libertação de cálcio mitocondrial (com uma
sonda fluorescente, Calcium Green-5N) e
respiração mitocondrial (com um eléctrodo
de oxigénio).
Resultados: O CV reduziu os danos
mitocondriais associados à produção de
espécies reactivas de oxigénio (ERO) pelos
prooxidantes, como verificado pela redução
no entumescimento mitocondrial e aumento
da capacidade de retenção do cálcio pela
mitocôndria. O CV melhorou ainda a
capacidade respiratória mitocondrial associada ao estado fosforilativo e aumentou
o Ãndice de controlo respiratório (p<0.05) e o
quociente ADP/O (p<0.001) das
mitocôndrias cardÃacas sob estresse oxidativo
induzido por HX/XO.
Conclusões: Os dados indicam que o CV
protegeu parcialmente a mitocôndria
cardÃaca de danos oxidativos induzidos por
HX/XO, o que poderá ser de grande
utilidade em situações de isquémiareperfusão
do miocárdio.
Os resultados também sugerem que a
mitocôndria poderá ser um alvo prioritário
para a acção benéfica de alguns fármacos
cardioprotectores.Objectives: The cardioprotective effects of
carvedilol (CV) may be explained in part by
interactions with heart mitochondria. The
objective of this work was to study the
protection afforded by CV against oxidative
stress induced in isolated heart mitochondria
by hypoxanthine and xanthine oxidase
(HX/XO), a well-known source of reactive
oxygen species (ROS) in the cardiovascular
system.
Methods: Mitochondria were isolated from
Wistar rat hearts (n=8) and incubated with
HX/XO in the presence and in the absence of
calcium. Several methods were used to assess
the protection afforded by CV: evaluation of
mitochondrial volume changes (by measuring
changes in the optical density of the
mitochondrial suspension), calcium uptake
and release (with a fluorescent probe, Calcium
Green 5-N) and mitochondrial respiration
(with a Clark-type oxygen electrode).
Results: CV decreased mitochondrial damage
associated with ROS production by HX and
XO, as verified by the reduction of mitochondrial swelling and increase in
mitochondrial calcium uptake. In the
presence of HX and XO, CV also
ameliorated mitochondrial respiration in the
active phosphorylation state and prevented
decrease in the respiratory control ratio
(p<0.05) and in mitochondrial
phosphorylative efficiency (p<0.001).
Conclusions: The data indicate that CV
partly protected heart mitochondria from
oxidative damage induced by HX and XO,
which may be useful during myocardial
ischemia and reperfusion. It is also
suggested that mitochondria may be a
priority target for the protective action of
some compounds
Semi-pelagic Longline and Trammel Net Elasmobranch Catches in Southern Portugal: Catch Composition, Catch Rates and Discards
In Portugal, elasmobranch landings have decreased substantially in recent years. In this work,
elasmobranch catches in semi-pelagic longlines (1997 and 1998) were compared with those in trammel
nets (2000) in the Algarve, southern Portugal areas. In the semi-pelagic longline fi shery, 7 elasmobranch
species represented 33.4% (2 185 specimens) of the total fi sh catches. Among the elasmobranch species,
the most abundant were Galeus melastomus (63.3%), Etmopterus pusillus (21.7%) and Scyliorhinus
canicula (14.2%). Most of these elasmobranchs were discarded (68.3% in total). In the trammel net
fi shery, 16 different elasmobranch species represented 4.3% (597 specimens) of total fi sh catches and
the most important species were Raja undulata (43.6%) and S. canicula (10.2%). The majority of
the elasmobranchs caught in trammel nets had commercial value, and only 5.4% were discarded. In
both fi sheries, intra-specifi c catch rates varied with depth. Length-frequency distributions for the only
species with relatively high catches in both fi sheries, S. canicula, showed that, in general, trammel
nets catch larger specimens and in a narrower length range than do longlines.info:eu-repo/semantics/publishedVersio
Carvedilol: Relation Between Antioxidant Activity and Inhibition of the Mitochondrial Permeability Transition
Objectivos: A transição de permeabilidade
mitocondrial (TPM) é um evento associado a
estresse oxidativo severo (por exemplo,
durante isquémia e reperfusão do miocárdio)
e acumulação excessiva de cálcio
mitocondrial, podendo mesmo levar a morte
celular. Neste estudo comparou-se o efeito
do Carvedilol (CV) na TPM cardÃaca
induzida por cálcio/fosfato (Ca/Pi) e
cálcio/carboxiatractilato (Ca/Catr). Para a
indução da TPM por Ca/Pi, o estresse
oxidativo tem um papel importante, levando
a oxidação de grupos tiólicos proteicos
mitocondriais, em contraste com o efeito do
Ca/Catr, onde essa oxidação é secundária Ã
indução da TPM e não é motivada por
estresse oxidativo.
Materiais e métodos: As mitocôndrias foram
isoladas a partir do coração de rato e
avaliaram-se parâmetros relacionados com a
indução da TPM (n=5 para cada indutor):
entumescimento mitocondrial e oxidação dos
grupos tiólicos proteicos (ambos por
espectrofotometria).
Resultados: Com Ca/Pi, o CV protegeu a
mitocôndria da indução da TPM,
nomeadamente na sua forma deletéria de alta
condutância. Este efeito evidenciou-se pela
diminuição do entumescimento mitocondrial.
Este efeito foi simultâneo com a inibição da
oxidação dos grupos tiólicos proteicos carmitocondriais
(p<0.001). O CV não mostrou
efeitos protectores com Ca/Catr.
Conclusões: O CV protegeu a mitocôndria
cardÃaca da TPM, mas apenas quando a
oxidação dos grupos tiólicos proteicos foi
causa e não consequência da TPM. Estes
resultados mostram claramente que, durante
agressões ao miocárdio (durante a
isquémia/reperfusão, por exemplo), o efeito
protector do CV é primariamente devido a
um efeito antioxidante, inibindo a produção
e os efeitos das espécies reactivas de
oxigénio.Objectives: The mitochondrial permeability
transition (MPT) is an event related to severe
oxidative stress (for example, during
myocardial ischemia and reperfusion) and
excessive mitochondrial calcium
accumulation, also being implicated in cell
death. In this study, we compared the effect
of carvedilol on the cardiac MPT induced by
calcium and phosphate (Ca/Pi) and
calcium/carboxyatractyloside (Ca/Catr).
Oxidative stress plays a major role in MPT
induction by Ca/Pi, leading to the oxidation
of protein thiol groups, in contrast with
Ca/Catr, where such oxidation is secondary
to MPT induction and is not caused by
oxidative stress.
Materials and methods: Mitochondria were
isolated from rat hearts and parameters
related to MPT induction were evaluated
(n=5 for each inducer): mitochondrial
swelling and oxidation of protein thiol groups
(both measured by spectrophotometry).
Results: Using Ca/Pi, carvedilol protected
mitochondria from MPT induction,
particularly in its high conductance form. Its
effect was demonstrated by analyzing the
decrease in mitochondrial swelling
amplitude. Simultaneously, we observed inhibition of protein thiol group oxidation
(p<0.001). By contrast, carvedilol did not
show any protective effect with Ca/Catr.
Conclusions: Carvedilol was only effective
against the MPT when the oxidation of
protein thiol groups was the cause and not
the consequence of the MPT phenomenon.
The results clearly show that during
myocardial aggressions (ischemia and
reperfusion, for example), the protective
effect of carvedilol is primarily due to an
antioxidant mechanism, inhibiting the
production and effects of reactive oxygen
species
Competition between static gear of the small-scale fisheries in Algarve waters (southern Portugal)
Parallel fishing trials with 0.30 mm diameter monofilament gill nets and longlines using small hooks were carried out in the Algarve (southern Portugal) over a one-year period, 1997-1998, with the objective of comparing species composition, catch rates, discards and size ranges. Four hook sizes of MUSTAD brand, round bent, flatted sea hooks (numbers 15, 13, 12 and 11) and four mesh sizes of 50, 60, 70, and 80 (stretched mesh) (nominal bar length) of gill nets were used in the trials. Overall, 84 species were caught, with gill nets taking 71 species and longlines 54 species and with 41 species caught by both gear types. The amount of discarding was higher for gill nets than for longlines. The catch species composition differed between the two gear types, with the commercially valuable sea breams dominating the longline catches whereas small pelagics were relatively more important in the gill nets. Multivariate analysis showed a clear separation between the different sizes of the two gear types both in terms of numbers and weights per species. Algarve gill netters and longliners fish the same species assemblage on the same fishing grounds, but have clearly different impacts in terms of catch species composition, catch rates and sizes. This information will be useful for the improved management of these small-scale, multi-species, multi-gear fisheries, where different gear types compete for scarce resources. In particular this study provides a basis for a more rational allocation of licenses and control of fishing effort
Age, growth and reproduction of the Axilary Seabream, "Pagellus acarne" (Risso, 1827), from the South coast of Portugal
Axillary seabream, Pagellus acarne, caught by longlines in the Algarve (Southern Portugal), were
sampled between August 1995 and August 1996. Age was studied by counting growth increments on otoliths
and the estimated von Bertalanffy parameters were Linf = 28.82 cm, K = 0.29 year-1 and t0 = -1.47 year for
males and Linf = 32.30 cm, K = 0.18 year-1 and t0 = -2.56 year for females. Evidence of the annual periodicity of
the deposition of increments was found by marginal increment analyses. Macroscopic analysis of the
gonads and the gonad somatic index showed that reproduction occurred over an extensive period of
time, from May to November. Lengths at first maturity were 18.10 and 17.60 cm for males and females,
respectively. This species was characterized as being a protandric hermaphrodite.info:eu-repo/semantics/publishedVersio
A Clinical Decision Support System for Remote Monitoring of Cardiovascular Disease Patients: A Clinical Study Protocol
Funding: This work was partially supported by the Center for Innovative Care and Health Technology (ciTechcare), Polytechnic of Leiria, Portugal. The work of FV was funded by the Portuguese Foundation for Science and Technology (FCT), CEECINST/00103/2018. The funder had no role in the clinical study protocol.Introduction: Cardiovascular diseases (CVD) are the leading cause of death globally, taking an estimated 17. 9 million lives each year. Cardiac rehabilitation is shown to reduce mortality and hospital readmissions, while improving physical fitness and quality of life. Despite the recommendations and proven benefits, acceptance and adherence remain low. Mobile health (mHealth) solutions may contribute to more personalized and tailored patient recommendations according to their specific needs. This study protocol aims to assess the effectiveness of a user-friendly, comprehensive Clinical Decision Support System (CDSS) for remote patient monitoring of CVD patients, primarily on the reduction of recurrent cardiovascular events. Methods and Analysis: The study will follow a multicenter randomized controlled design involving two cardiology units in the Center Region of Portugal. Prospective CVD patients will be approached by the healthcare staff at each unit and checked for eligibility according to the predefined inclusion/exclusion criteria. The CDSS will suggest a monitoring plan for the patient, will advise the mHealth tools (apps and
wearables) adapted to patient needs, and will collect data. The clinical study will start in January 2023.
Discussion: The success of the mHeart.4U intervention will be a step toward the use of technological interfaces as an integrating part of CR programs. Ethics and Dissemination: The study will undergo ethical revision by the Ethics Board of the two hospital units where the study will unfold. The study was registered
in ClinicalTrials.gov on 18th January 2022 with the number NCT05196802. The study findings will be published in international peer-reviewed scientific journals and encounters and in a user-friendly manner to the society.info:eu-repo/semantics/publishedVersio
Portable art and personal ornaments from Txina-Txina: a new later stone age site in the Limpopo River Valley, southern Mozambique
This paper reports on preliminary fieldwork at the Later Stone Age site of Txina-Txina in Mozambique. Excavation yielded a long stratigraphic sequence, a large lithic assemblage, a unique decorated gastropod shell fragment and two ostrich eggshell beadsthe first of their type recovered from a Stone Age context in Mozambique.Fundacao para a Ciencia e Tecnologia [PTDC/EPH-ARQ/4998/2012, PTDC/EPHARQ/4168/2014]; National Geographic Society [W373.15, HJ-033R-17
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