Influence of sex, maturity and reproduction on PCB and p,p'DDE concentrations and repartitions in the European hake (Merluccius merluccius, L.) from the Gulf of Lions (N.W. Mediterranean).

Science.gov (United States)

Bodiguel, Xavier; Loizeau, Véronique; Le Guellec, Anne-Marie; Roupsard, François; Philippon, Xavier; Mellon-Duval, Capucine

2009-12-20

The main objective of this work was to establish the influence of sex, maturity and reproduction on the contamination of the demersal fish Merluccius merluccius by organochlorine compounds. Polychlorinated biphenyls (PCBs) and p,p'DDE were quantified in muscle, liver and gonads of female and male hakes collected in the Gulf of Lions in 2004 and 2005. Observed levels appeared higher than the population of the Bay of Biscay and lower than the population of the Thyrrenian Sea. Contaminant fingerprints were roughly constant whatever the studied organ and the hake biological condition. Concentrations varied significantly according to the sex and maturity of hakes. Mature specimens were more contaminated than immature, and males presented higher levels than females. This sex effect can be linked to a lower growth rate of males, and a contaminant elimination during female spawning. Gonadal contamination depends on the importance of lipid content and increases with the maturation degree. Although the main organ of energy and PCB storage is the liver, muscle appears as the main contributor to the gonad contamination.

A multitracer approach to assess the spatial contamination pattern of hake (Merluccius merluccius) in the French Mediterranean.

Science.gov (United States)

Cresson, Pierre; Bouchoucha, Marc; Morat, Fabien; Miralles, Francoise; Chavanon, Fabienne; Loizeau, Veronique; Cossa, Daniel

2015-11-01

Chemical contamination levels and stable isotope ratios provide integrated information about contaminant exposure, trophic position and also biological and environmental influences on marine organisms. By combining these approaches with otolith shape analyses, the aim of the present study was to document the spatial variability of Hg and PCB contamination of the European hake (Merluccius merluccius) in the French Mediterranean, hypothesizing that local contaminant sources, environmental conditions and biological specificities lead to site-specific contamination patterns. High Hg concentrations discriminated Corsica (average: 1.36 ± 0.80 μg g(-1) dm) from the Gulf of Lions (average valuesLions, whatever the sex of the individuals, whereas the highest values in Corsica were 6.75 ± 4.22 ng g(-1) dm. Otolith shape discriminated juveniles and adults, due to their different habitats. The use of combined ecotracers was revealed as a powerful tool to discriminate between fish populations at large and small spatial scale, and to enable understanding of the environmental and biological influences on contamination patterns. Copyright © 2015 Elsevier B.V. All rights reserved.

A multitracer approach to assess the spatial contamination pattern of hake (Merluccius merluccius) in the French Mediterranean

International Nuclear Information System (INIS)

Cresson, Pierre; Bouchoucha, Marc; Morat, Fabien; Miralles, Francoise; Chavanon, Fabienne; Loizeau, Veronique; Cossa, Daniel

2015-01-01

Chemical contamination levels and stable isotope ratios provide integrated information about contaminant exposure, trophic position and also biological and environmental influences on marine organisms. By combining these approaches with otolith shape analyses, the aim of the present study was to document the spatial variability of Hg and PCB contamination of the European hake (Merluccius merluccius) in the French Mediterranean, hypothesizing that local contaminant sources, environmental conditions and biological specificities lead to site-specific contamination patterns. High Hg concentrations discriminated Corsica (average: 1.36 ± 0.80 μg g −1 dm) from the Gulf of Lions (average values < 0.5 μg g −1 dm), where Rhône River input caused high PCB burdens. CB 153 average concentrations ranged between 4.00 ± 0.64 and 18.39 ± 12.38 ng g −1 dm in the Gulf of Lions, whatever the sex of the individuals, whereas the highest values in Corsica were 6.75 ± 4.22 ng g −1 dm. Otolith shape discriminated juveniles and adults, due to their different habitats. The use of combined ecotracers was revealed as a powerful tool to discriminate between fish populations at large and small spatial scale, and to enable understanding of the environmental and biological influences on contamination patterns. - Highlights: • Hg and PCB concentrations were assessed in French Mediterranean hake. • Stable isotope and otolith shape analyses were used in combination. • Local isotopic and contamination patterns were observed. • Hg values were high in Corsica, PCB in the Gulf of Lions. • Combined ecotracers are powerful to discriminate between local populations

A multitracer approach to assess the spatial contamination pattern of hake (Merluccius merluccius) in the French Mediterranean

Energy Technology Data Exchange (ETDEWEB)

Cresson, Pierre, E-mail: pierre.cresson@ifremer.fr [Ifremer, RHMN, Centre Manche — Mer du Nord, BP 669, F-62 321 Boulogne sur Mer (France); Ifremer, LER/PAC, Centre de Méditerranée, CS 20330, F-83 507 La Seyne sur Mer (France); Bouchoucha, Marc [Ifremer, LER/PAC, Centre de Méditerranée, CS 20330, F-83 507 La Seyne sur Mer (France); Morat, Fabien [IRSTEA, 3275 Route Cézanne, CS 40061, F-13 182 Aix en Provence Cedex 5 (France); Miralles, Francoise; Chavanon, Fabienne [Ifremer, LER/PAC, Centre de Méditerranée, CS 20330, F-83 507 La Seyne sur Mer (France); Loizeau, Veronique [Ifremer, LBCO, Centre Atlantique, BP 70, F-29 280 Plouzané (France); Cossa, Daniel [ISTerre, Université Joseph Fourier, BP 53, F-38 041 Grenoble (France)

2015-11-01

Chemical contamination levels and stable isotope ratios provide integrated information about contaminant exposure, trophic position and also biological and environmental influences on marine organisms. By combining these approaches with otolith shape analyses, the aim of the present study was to document the spatial variability of Hg and PCB contamination of the European hake (Merluccius merluccius) in the French Mediterranean, hypothesizing that local contaminant sources, environmental conditions and biological specificities lead to site-specific contamination patterns. High Hg concentrations discriminated Corsica (average: 1.36 ± 0.80 μg g{sup −1} dm) from the Gulf of Lions (average values < 0.5 μg g{sup −1} dm), where Rhône River input caused high PCB burdens. CB 153 average concentrations ranged between 4.00 ± 0.64 and 18.39 ± 12.38 ng g{sup −1} dm in the Gulf of Lions, whatever the sex of the individuals, whereas the highest values in Corsica were 6.75 ± 4.22 ng g{sup −1} dm. Otolith shape discriminated juveniles and adults, due to their different habitats. The use of combined ecotracers was revealed as a powerful tool to discriminate between fish populations at large and small spatial scale, and to enable understanding of the environmental and biological influences on contamination patterns. - Highlights: • Hg and PCB concentrations were assessed in French Mediterranean hake. • Stable isotope and otolith shape analyses were used in combination. • Local isotopic and contamination patterns were observed. • Hg values were high in Corsica, PCB in the Gulf of Lions. • Combined ecotracers are powerful to discriminate between local populations.

Myxozoans as biological tags for stock identification of the Argentine hake, Merluccius hubbsi (Gadiformes: Merlucciidae)

Czech Academy of Sciences Publication Activity Database

Cantatore, D.M.P.; Irigoitia, M.M.; Holzer, Astrid S.; Timi, J.T.

2016-01-01

Roč. 143, č. 6 (2016), s. 732-740 ISSN 0031-1820 Institutional support: RVO:60077344 Keywords : biological markers * Kudoa rosenbuschi * Myxoproteus meridionalis * Fabespora sp. * common hake * stock discrimination * South West Atlantic Subject RIV: EH - Ecology, Behaviour Impact factor: 2.713, year: 2016

Argyrosomus hololepidotus, Pomatomus saltatrix and Merluccius ...

African Journals Online (AJOL)

saltatrix (elf) and Merluccius capensis (Shallow-water hake) between Algoa Bay ... deep-water species such as Merluccius capensis is well known. (Botha 1971; Botha ...... B. Davie in collecting and processing the material is acknowledged.

Age estimation of juvenile European hake Merluccius merluccius based on otolith microstructure analysis: a slow or fast growth pattern?

Science.gov (United States)

Pattoura, P; Lefkaditou, E; Megalofonou, P

2015-03-01

The main goal of this study was to examine otolith microstructure and to estimate the age and growth of European hake Merluccius merluccius from the eastern Mediterranean Sea. One hundred and twenty-nine specimens ranging from 102 to 438 mm in total length (LT ) were used. Age estimations were based on the study of the otolith microstructure, which was revealed after grinding both frontal sides of otoliths. The enumerations of the daily growth increments (DGI) as well as their width (WDGI ) measurements were made on calibrated digital images. The number of DGI in otoliths ranged between 163 and 717. Four phases in the WDGI evolution were distinguished: (1) larval-juvenile pelagic phase, with an increasing trend in WDGI up to the 60th DGI, (2) settlement phase, with a short-term deceleration in WDGI between the 61st and 150th DGI, (3) juvenile demersal phase, characterized by a stabilization of WDGI from 151st to 400th DGI and (4) adult phase, with a decreasing trend in WDGI after the 400th DGI. Age, sex and month of formation were found to affect the WDGI in all phases, with the exception of age at the juvenile demersal phase. The power curve with intercept model described best the relationship of M. merluccius LT with age (TDGI ), according to Akaike criteria, revealing differences in growth between females [LT = 65 · 36(TDGI )(0 · 40) - 388 · 55] and males [LT = 69 · 32(TDGI )(0 · 37) - 352 · 88] for the sizes examined. The mean daily growth rates were 0·61 mm day(-1) for females and 0·52 mm day(-1) for males, resulting in an LT of 283 and 265 mm at the end of their first year of life. In comparison with previous studies on the Mediterranean Sea, the results of this study showed a greater growth rate, similar to results from tagging experiments and otolith microstructure analyses for M. merluccius in other geographic areas. © 2014 The Fisheries Society of the British Isles.

Migration, distribution and population (stock) structure of shallow-water hake (Merluccius capensis) in the Benguela Current Large Marine Ecosystem inferred using a geostatistical population model

DEFF Research Database (Denmark)

Jansen, Teunis; Kristensen, Kasper; Kainge, Paulus Inekela

2016-01-01

Shallow-water hake (Merluccius capensis) is of considerable ecological and economic importance in the Benguela Current Large Marine Ecosystem in South Africa and Namibia. Optimal management of the resource is currently constrained by the limited understanding of migration patterns and population...

The impact of overfishing and El Niño on the condition factor and reproductive success of Peruvian hake, Merluccius gayi peruanus

Science.gov (United States)

Ballón, Michael; Wosnitza-Mendo, Claudia; Guevara-Carrasco, Renato; Bertrand, Arnaud

2008-10-01

In this study we examine physiological responses of Peruvian hake ( Merluccius gayi peruanus) to changes in their population structure and physical environment during the period 1971-2004. In particular, we assess the relative investment of energy in growth and/or reproduction of small (20-35 cm) and large (35-50 cm) hake. We calculated the (i) condition (Fulton’s K), (ii) gonad and (iii) gut fullness indices for 42,761 female hakes sampled from commercial landings; these indices indicate fish somatic, reproductive and feeding condition, respectively. Using Generalized Additive Models we then examined potential relationships between these indices and sea surface temperature anomalies and date. Drastic energy exhaustion and a decrease in female hake fecundity were observed during El Niño events. The long-term trend showed a general increase in condition factor and a decrease in gonad index for large hake between 1971 and 2004. Small hake exhibited a different trend with an increase in reproductive activity, which was accompanied by an earlier maturation. We hypothesise that the observed low investment of energy in reproduction by large female hake might be related to the lack of large males, due to a sex-selective fishery and the impact of El Niño. We suggest that fishing diminished hake reproductive capacity, modified the sex ratio in favour of females and increased population vulnerability to environmental stress, in particular to the El Niño. The impact of multidecadal variability and predators like the squid, Dosidicus gigas, remain unresolved until longer time series become available.

Pacific Hake - Growth and natal origin of Pacific hake from the Georgia Basin DPS

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Pacific hake (Merluccius productus) is an abundant species residing along the Pacific coast from the Gulf of California to the Strait of Georgia. It is the most...

Two hake species, deep-water Cape hake Merluccius paradoxus ...

African Journals Online (AJOL)

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paradoxus and shallow-water Cape hake M. capensis, are found along the ... For both species, average length increased with depth. M. paradoxus expanded its ..... Evolution of the Benguela, physical features and processes. In Oceano-.

Adaptive response of Peruvian Hake to overfishing

OpenAIRE

Mendo, C.W.; Carrasco, R.G.

2000-01-01

Compensatory mechanisms of the Peruvian hake population (Merluccius gayi peruanus) in response to heavy exploitation and changes in species interaction are discussed. Changes in the rate of cannibalism, diet composition, maximization of fecundity and behavioral adaptation are noted.

Efecto de la incorporación de transglutaminasa microbiana en las propiedades sensoriales de hamburguesas de desmenuzado de merluza (Merluccius hubbsi

Directory of Open Access Journals (Sweden)

Alicia Panuncio

2013-12-01

Full Text Available Se elaboraron hamburguesas de pescado a partir de desmenuzado de merluza (Merluccius hubbsi con la incorporación de transglutaminasa microbiana, con la finalidad de mejorar sus propiedades sensoriales y elaborar un producto pesquero que fomente el consumo de pescado en Uruguay. Se evaluó desde el punto de vista sensorial y de textura instrumental el efecto del agregado de la enzima en la formulación de las hamburguesas. Se elaboraron tres tipos de hamburguesas: sin enzima y con incorporación de 0,5% y 1,0% de enzima transglutaminasa, respectivamente. Para la evaluación sensorial se analizaron las muestras con un panel de seis jueces entrenados y para la determinación de los parámetros de textura instrumental se utilizó un analizador de textura TA.XT2i. Los resultados de ambos estudios indicaron que el agregado de enzima mejoró sustancialmente la apariencia, la textura y el sabor del producto. Se obtuvo un producto pesquero innovador, con características que pueden resultar muy atractivas para el consumidor uruguayo.

Spawning of the chilean hake (Merluccius gayi in the upwelling system off Talcahuano in relation to oceanographic features

Directory of Open Access Journals (Sweden)

Cristian A. Vargas

2001-06-01

Full Text Available Previous studies have shown that the upwelling area off Talcahuano, in central-south Chile, is an important spawning zone for the hake Merluccius gayi. We document the results of a study designed to assess the importance of oceanographic features on the horizontal and vertical distribution of hake eggs and larvae. Ichthyoplankton samples and oceanographic data (CTDO casts, and wind speed and direction were collected during a cruise carried out off Talcahuano (36º22´S-37º10´S in early spring (October 1996, which included a grid of 61 stations up to 60 nm offshore. The oceanographic information obtained revealed the presence of an upwelling plume at Lavapie Point (southern zone extending northward over the shelf, and the presence of a warmer water parcel close to shore in the northern area. Peak egg densities occurred in this northern area over the shelf, in a nucleus located at the shoreward moving deeper layer (40-100 m deep and associated with the upwelling front about 20-30 nm from shore. The highest larval abundance also occurred in the northern area over the shelf and in the deeper layer but closer to shore than the egg nucleus. Because the timing (early spring and location of spawning (at depth, over the shelf and in association with frontal structures are also shared by other hake species in upwelling areas, we propose that they may be part of a more commonly developed strategy to enhance offspring survival in coastal upwelling areas of eastern boundary currents.

Avoidance within a changing assessment paradigm for Mediterranean Hake stocks

Directory of Open Access Journals (Sweden)

S. RAGONESE

2009-06-01

Full Text Available The Mediterranean hake Merluccius merluccius L., 1758, is the emblem of the so-called Mediterranean demersal fisheries paradox, showing a persistent, although stable, status of growth overexploitation and an impressive gap between current and any biological reference point. Almost full avoidance capability of large size females to bottom trawls, higher overall growth rates than previously believed and higher natural mortality in juveniles than adult, were considered among the most plausible explanation factors of such persistence. In the present note, arguments are illustrated to raise some concern about avoidance and highlight the important role of the other factors in improving assessments and launching a short term recovery plan for Mediterranean Hake stocks which is more acceptable to fishermen.

Cape hake Merluccius capensis and M. paradoxus in southern ...

African Journals Online (AJOL)

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knowledge of the behaviour of Cape hake in general. ... Ministry of Fisheries and Marine Resources, National Marine Information and Research Centre, P.O. Box 912, Swakopmund, Namibia. E-mail: ... (BEI) post-processing system, which allows for better ..... deep water, where hake density is generally low and.

Novel Tools for Conservation Genomics: Comparing Two High-Throughput Approaches for SNP Discovery in the Transcriptome of the European Hake

DEFF Research Database (Denmark)

Milano, Ilaria; Babbucci, Massimiliano; Panitz, Frank

2011-01-01

The growing accessibility to genomic resources using next-generation sequencing (NGS) technologies has revolutionized the application of molecular genetic tools to ecology and evolutionary studies in non-model organisms. Here we present the case study of the European hake (Merluccius merluccius),...

Emergence of a new predator in the North Sea: evaluation of potential trophic impacts focused on hake, saithe, and Norway pout

DEFF Research Database (Denmark)

Cormon, Xochitl; Kempf, Alexander; Vermard, Youen

2016-01-01

During the last 15 years, northern European hake (Merluccius merluccius) has increased in abundance, and its spatial distribution has expanded in the North Sea region in correlation with temperature. In a context of global warming, this spatial shift could impact local trophic interactions: direc...

Determination of effective effort on hake Merluccius merluccius in a Mediterranean trawl fishery

Directory of Open Access Journals (Sweden)

Francisco Alemany

2003-12-01

Full Text Available The direct control of fishing effort as a management tool is of special interest in the Mediterranean, where the lack of effective international management systems and the high diversity of the catches significantly increases the complexity of implementing TAC´s as an indirect control of fishing effort. However, its enforcement should be based on the precise knowledge of the relationship between the fishing effort and its corresponding fishing mortality. In this sense, the general aim of this study was to develop an approach for analysing this relationship. In order to estimate the annual effective fishing effort on hake, a relational data base including daily landings by vessel and species of trawl fleet based on the port of Palma, Mallorca island (western Mediterranean during the period 1983-1991 was built. Fishing mortalities were available from VPA. Fishing effort and fishing mortality were split by subfleets or métiers which were identified by cluster analysis. Significant linear relationships between the two parameters were obtained when fishing effort was considered as the number of days in which hake catch was higher than 10 kg multiplied by GRT of correspondent vessels. These CPUE values are mainly obtained when trawlers operate in the muddy bottoms of the shelf and on the upper slope, where hake populations are mostly distributed. On the other hand, no clear trends in catchability by métier were found during the period analysed.

Occurrence of mislabelling in prepared fishery products in Southern Italy

Directory of Open Access Journals (Sweden)

Giuseppina Tantillo

2015-09-01

Full Text Available Fish authentication is a major concern not only for the prevention of commercial fraud, but also for the assessment of safety risks deriving from the undeclared introduction of potentially dangerous toxic or allergenic substances or environmentally damaging fish where endangered species are involved. Moreover, food authentication might affect the diet of certain groups of consumers, such as followers of religious practices. Considering the authentication of fish products is one of the key issues in food safety, quality and sustainability, the aim of this work was to investigate the prevalence of mislabelling in sole (Solea solea, plaice (Pleuronectes platessa, Atlantic salmon (Salmo salar, and hake (Merluccius merluccius fillets from markets and supermarkets located in Apulia (Southern Italy using DNA barcoding. The results of the molecular investigations reveal that 42/98 (42.8% fillet samples were not correctly labelled. In particular, 12/27 (44.4% fillets of sole (Solea solea were identified as belonging to Solea senegalensis. In addition, 13/28 (46.4% plaice (Pleuronectes platessa samples were identified as Pangasius hypophtalmus. All Atlantic salmon (Salmo salar samples were correctly labelled. Post-sequencing data analysis revealed that 17/30 (56.6% hake fillets (Merluccius merluccius were not correctly labelled, of which 8/30 samples identified as Merluccius hubbsi, 5/30 samples as Merluccius products and 4/30 as Merluccius capensis. The study reveals a high occurrence of species mislabelling in the prepared fish fillet products, further evidence of the need for increased traceability and assessment of the authenticity of food products.

Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean

International Nuclear Information System (INIS)

Harmelin-Vivien, Mireille; Bodiguel, Xavier; Charmasson, Sabine; Loizeau, Véronique; Mellon-Duval, Capucine; Tronczyński, Jacek; Cossa, Daniel

2012-01-01

Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and 137 Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism’s trophic level (δ 15 N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and 137 Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.

Radioactivity levels in peruvian hake Merluccius gayi peruanus (Guitchenot)

International Nuclear Information System (INIS)

Osores, Jose

2014-01-01

The aim of this study was to determine background levels of natural and artificial radionuclides in Peruvian hakes, collected in the Pacific coast of Peru, as a mechanism to establish a biomonitoring model for human radiation exposure resulting from the ingestion of this species. The concentration range overall dry weight of beta activity was between 39 and 79 Bq/kg; for K-40, the range was between 66 and 116 Bq/kg and for Cs-137, the range was between 0.0 and 0.4 Bq/kg. No detectable levels of Co-60, Cs-134 and Ra-226 were found. The dose derived from K-40 was negligible. Data show that Peruvian hakes do not represent a public health risk because of their intake as food. (author).

Integrated response of antioxidant biomarkers in the liver and white muscle of European hake (Merluccius merluccius L. females from the Adriatic sea with respect to environmental influences

Directory of Open Access Journals (Sweden)

Pavlović Slađan Z.

2018-01-01

Full Text Available We investigated the integrated response of antioxidant defense enzymes (total superoxide dismutase (TotSOD, manganese-containing superoxide dismutase (MnSOD, copper-zinc-containing superoxide dismutase (CuZnSOD, catalase (CAT, glutathione peroxidase (GSH-Px, glutathione reductase (GR and phase II biotransformation enzyme, glutathione- S-transferase (GST in the liver and white muscle of females of European hake (Merluccius merluccius L. from the Adriatic Sea (Montenegro in winter and spring. The activity of GSH-Px in the liver was significantly increased, while GST activity was decreased in spring compared to the winter. In white muscle, the activities of TotSOD and CuZnSOD were increased, while the activities of MnSOD, CAT, GSH-Px, GR and GST were decreased in spring when compared to the matching values in winter. The activities of TotSOD and CuZnSOD in winter were markedly lower in the muscle than in the liver, while the activity of MnSOD in the muscle was higher when compared to the liver. Principal component analysis (PCA revealed clear separation of the investigated antioxidant biomarkers between tissues and seasons, while the integrated biomarker response (IBR showed that the most intensive antioxidant biomarker response was in the liver in spring. Star plots of IBR showed a dominant contribution of glutathione-dependent biomarkers (GSH-Px, GR and GST and CAT in both tissues and seasons with respect to SOD isoenzymes. All enzyme activities (except MnSOD were greater in the liver in comparison to the white muscle. Our results show that the liver possesses a greater capacity to establish and maintain homeostasis under changing environmental conditions in winter and spring. At the same time, seasonal effects are more pronounced in muscle tissue. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 173041

Escapement of Cape hakes under the fishing line of the Namibian ...

African Journals Online (AJOL)

The objective of this study was to establish whether Cape hakes Merluccius capensis and M. paradoxus escape under the fishing line and to identify any species or length dependence of escape rates. Experiments were carried out in Namibian waters during two cruises in October 2002 and October 2003. A collection bag ...

Evaluation of some physico-chemical properties of restructured trout and hake mince during cold gelation and chilled storage

DEFF Research Database (Denmark)

Moreno, H.M.; Javier Borderias, A.; Baron, Caroline

2010-01-01

Cold gelation was carried out on trout (Oncorhynchus mykiss) or on hake (Merluccius mertuccius) mince with or without addition of fish oil and using microbial transglutaminase (MTGase). Products were stored at 4 QC for 6 days and lipid oxidation, protein oxidation, texture, water binding capacity......, and colour were followed. Results indicated that MTGase was able to generate gels with good properties for both trout and hake. Gels prepared with trout were oxidised whilst gels prepared with hake were stable toward oxidation even in the presence of 5% fish oil. However, in the presence of oil...

Radioactive zinc ( sup 65 Zn), zinc, cadmium, and mercury in the Pacific Hake, Merluccius productus (Ayres), off the West Coast of the United States

Energy Technology Data Exchange (ETDEWEB)

Naidu, J.R.

1974-06-01

The Pacific Hake, Merluccius productus (Ayers) was used to monitor the waters off Puget Sound and the West Coast of the US for zinc(Zn), cadmium(Cd), mercury(Hg) and {sup 65}Zn. The Columbia River is not the source of Zn, Cd or Hg contamination, but is the source of {sup 65}Zn, with the concentration in the Hake reflecting the position of the Columbia River plume. Zn and Cd accumulation in the Hake were fit to the equation Y=B{sub 1}+B{sub 2}e{sup B}{sub 3}X where Y is the concentration of the element and X is the length or weight of the fish. Biological attributes were assigned to the other parameters as follows: B{sub 1} is the asymptotic value for Zn or Cd at chemical maturity; B{sub 2} is the location of the curve with respect to the length or weight of the fish; and B{sub 3} is a constant pertaining to the rate of change of Zn or Cd. Although Zn, Cd and Hg are all Group 2B elements, only the concentrations of Zn and Cd were correlated for all locations; Hg concentrations varied as a function of location. Zn and Cd concentrations increase with fish size and approach an asymptotic value at maturity, while Hg concentrations were linear and the slope is a function of sampling location. Zn and Cd levels are regulated in the adult, while Hg continues to increase with age. It may be significant that the age distribution of fish caught commercially coincides with the maximum concentration of Zn and Cd. 195 refs., 30 figs., 10 tabs. (MHB)

Integrating microsatellite DNA markers and otolith geochemistry to assess population structure of European hake (Merluccius merluccius)

Science.gov (United States)

Tanner, Susanne E.; Pérez, Montse; Presa, Pablo; Thorrold, Simon R.; Cabral, Henrique N.

2014-04-01

Population structure and natal origins of European hake were investigated using microsatellite DNA markers and otolith geochemistry data. Five microsatellites were sequenced and otolith core geochemical composition was determined from age-1 hake collected in the northeast Atlantic Ocean and the Mediterranean Sea. Microsatellites provided evidence of a major genetic split in the vicinity of the Strait of Gibraltar, separating the Atlantic and the Mediterranean populations, with the exception of the Gulf of Cádiz. Based on classification models using otolith core geochemical values, individual natal origins were identified, although with an increased error rate. Coupling genotype and otolith data increased the classification accuracy of individuals to their potential natal origins while providing evidence of movement between the northern and southern stock units in the Atlantic Ocean. Information obtained by the two natural markers on population structure of European hake was complementary as the two markers act at different spatio-temporal scales. Otolith geochemistry provides information over an ecological time frame and on a fine spatial scale, while microsatellite DNA markers report on gene flow over evolutionary time scales and therefore act on a broader spatio-temporal resolution. Thus, this study confirmed the value of otolith geochemistry to complement the assessment of early life stage dispersal in populations with high gene flow and low genetic divergence.

The two species of Cape hake, Merluccius capensis (shallow-water ...

African Journals Online (AJOL)

denise

tinguish them in commercial catch statistics. Conse- ... and hence are taken incidentally in hake-directed fishing, instead of only species whose capture requires a different .... catch of these species is determined only at the landing site, and is ...

The two species of Cape hake, Merluccius capensis and M ...

African Journals Online (AJOL)

denise

are to be chosen by decision-makers, and adjust the TAC up or down from one year to the next according to whether trends in ... ment of the Nambian hake resource at that time was ...... Distribution medians, together with 90% probability.

Use of sand wave habitats by silver hake

Science.gov (United States)

Auster, P.J.; Lindholm, J.; Schaub, S.; Funnell, G.; Kaufman, L.S.; Valentine, P.C.

2003-01-01

Silver hake Merluccius bilinearis are common members of fish communities in sand wave habitats on Georges Bank and on Stellwagen Bank in the Gulf of Maine. Observations of fish size v. sand wave period showed that silver hake are not randomly distributed within sand wave landscapes. Regression analyses showed a significant positive relationship between sand wave period and fish length. Correlation coefficients, however, were low, suggesting other interactions with sand wave morphology, the range of current velocities, and available prey may also influence their distribution. Direct contact with sand wave habitats varied over diel periods, with more fish resting on the seafloor during daytime than at night. Social foraging, in the form of polarized groups of fish swimming in linear formations during crepuscular and daytime periods, was also observed. Sand wave habitats may provide shelter from current flows and mediate fish-prey interactions. ?? 2003 The Fisheries Society of the British Isles.

Caracterización de las principales pesquerías del golfo San Jorge Patagonia, Argentina Characterization of the main fisheries in San Jorge Gulf, Patagonia, Argentina

Directory of Open Access Journals (Sweden)

María Eva Góngora

2012-03-01

Full Text Available En el golfo San Jorge se desarrollan varias actividades económicas de relevancia, entre ellas dos pesquerías industriales: la pesquería de merluza común (Merluccius hubbsi Marini, 1933 y la pesquería de langostino patagónico (Pleoticus muelleri Bate, 1888, ambas se solapan espacial y temporalmente. En la pesquería de merluza del golfo San Jorge opera una flota fresquera de altura, compuesta por unas 20 embarcaciones, y una flota costera, compuesta por unas 30 embarcaciones. En esta pesquería se pesca alrededor del 10% de lo capturado en el stock sur de merluza. En la pesquería de langostino del golfo San Jorge opera una flota congeladora tangonera compuesta por 80 embarcaciones, responsable de más del 75% de los desembarques de langostino realizados en la República Argentina. Ambas pesquerías tienen como principal problema la captura incidental de merluza, en una de sus principales áreas de cría. En el presente trabajo se describe el manejo actual en las pesquerías del golfo San Jorge, el cual consiste principalmente en cierres espaciales y temporales para la pesca de langostino, y zonificaciones por estrato de flota para la merluza. En ninguna de las dos pesquerías descriptas se han tomado medidas que reduzcan eficazmente la captura incidental.In San Jorge Gulf, several important economic activities are developed, including two industrial fisheries: hake (Merluccius hubbsi Marini, 1933 and Argentine red shrimp (Pleoticus muelleri Bate, 1888. Both overlap spatially and temporally. The San Jorge Gulf hake fishery consists of a high-seas ice trawler fleet (n = 20 fishing vessels and a coastal fleet (n = 30 fishing vessels. These fisheries capture about 10% of the catch of the southern hake stock. The Argentine red shrimp fishery consists of a double-beam trawler fleet with 80 freezer vessels, responsible for more than 75% of shrimp landings in Argentina. The main problem of both fisheries is the bycatch of hake in one of its

Cooperation between scientists, NGOs and industry in support of sustainable fisheries: the South African hake Merluccius spp. trawl fishery experience.

Science.gov (United States)

Field, J G; Attwood, C G; Jarre, A; Sink, K; Atkinson, L J; Petersen, S

2013-10-01

This paper examines the increasingly close interaction between natural and social scientists, non-governmental organizations (NGO) and industry, in pursuit of responsible ecosystem-based management of fisheries. South Africa has committed to implementing an ecosystem approach to fisheries management. Management advice stems from multi-stakeholder representation on government-led scientific and management working groups. In the hake Merluccius capensis and Merluccius paradoxus fishery, the primary management measure is an annual total allowable catch (TAC), the level of which is calculated using a management procedure (MP) that is revised approximately every 4 years. Revision of the MP is a consultative process involving most stakeholders, and is based on simulation modelling of projected probable scenarios of resource and fishery dynamics under various management options. NGOs, such as the Worldwide Fund for Nature in South Africa (WWF-SA), have played an important role in influencing consumers, the fishing industry and government to develop responsible fishing practices that minimize damage to marine ecosystems. Cooperation between industry, government and scientists has helped to improve sustainability and facilitated the meeting of market-based incentives for more responsible fisheries. Research includes ecosystem modelling, spatial analysis and ecosystem risk assessment with increasing research focus on social and economic aspects of the fishery. A four-year cooperative experiment to quantify the effect of trawling on benthic community structure is being planned. The food requirements of top predators still need to be included in the TAC-setting formulae and more social and economic research is needed. This paper also demonstrates how NGO initiatives such as Marine Stewardship Council certification and the Southern African Sustainable Seafood Initiative, a traffic light system of classifying seafood for consumers, have contributed to responsible fishing

Effects of High-Pressure Treatment on the Muscle Proteome of Hake by Bottom-Up Proteomics.

Science.gov (United States)

Carrera, Mónica; Fidalgo, Liliana G; Saraiva, Jorge A; Aubourg, Santiago P

2018-05-02

A bottom-up proteomics approach was applied for the study of the effects of high-pressure (HP) treatment on the muscle proteome of fish. The performance of the approach was established for a previous HP treatment (150-450 MPa for 2 min) on frozen (up to 5 months at -10 °C) European hake ( Merluccius merluccius). Concerning possible protein biomarkers of quality changes, a significant degradation after applying a pressure ≥430 MPa could be observed for phosphoglycerate mutase-1, enolase, creatine kinase, fructose bisphosphate aldolase, triosephosphate isomerase, and nucleoside diphosphate kinase; contrary, electrophoretic bands assigned to tropomyosin, glyceraldehyde-3-phosphate dehydrogenase, and beta parvalbumin increased their intensity after applying a pressure ≥430 MPa. This repository of potential protein biomarkers may be very useful for further HP investigations related to fish quality.

Multi-sensor Oceanographic Correlations for Pacific Hake Acoustic Survey Improvement

Science.gov (United States)

Brozen, M.; Hillyer, N.; Holt, B.; Armstrong, E. M.

2010-12-01

North Pacific hake (Merluccius productus), the most abundant groundfish along the Pacific coast of northwestern America, are an essential source of income for the coastal region from southern California to British Columbia, Canada. However, hake abundance and distribution are highly variable among years, exhibiting variance in both the north-south and east-west distribution as seen in the results from biannual acoustic surveys. This project is part of a larger undertaking, ultimately focused on the prediction of hake distribution to improve the distribution of survey effort and precision of stock assessments in the future. Four remotely sensed oceanographic variables are examined as a first step in improving our understanding the relationship between the intensity of coastal upwelling and other ocean dynamics, and the north-south summer hake distribution. Sea surface height, wind vectors, chlorophyll - a concentrations, and sea surface temperature were acquired from several satellites, including AVHRR, SeaWifs, TOPEX/Poseidon, Jason-1, Jason-2, SSM/I, ASMR-E, and QuikScat. Data were aligned to the same spatial and temporal resolution, and these re-gridded data were then analyzed using empirical orthogonal functions (EOFs). EOFs were used as a spatio-temporally compact representation of the data and to reduce the co-variability of the multiple time series in the dataset. The EOF results were plotted and acoustic survey results were overlaid to understand differences between regions. Although this pilot project used data from only a single year (2007), it demonstrated a methodology for reducing dimensionality of linearly related satellite variables that can used in future applications, and provided insight into multi-dimensional ocean characteristics important for hake distribution.

Acoustical Scattering, Propagation, and Attenuation Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake

Science.gov (United States)

2015-09-30

an area important for acoustical testing and tactical exercises, the most abundant species by biomass is Pacific hake, Merluccius productus, a fish...scattering characteristics of the animal especially if the animal has eaten hard- shelled mollusc prey. Figure 7. A dorsal scan (similar to an x-ray) of a...kHz echogram. 11 In order to generate abundance and biomass estimates for organisms using active acoustics, one assumption that can be made is

MICROBIOLOGICAL EFFECTS OF ON-BOARD FISHING VESSEL HANDLING IN MERLUCCIUS MERLUCCIUS

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P. Serratore

2011-01-01

Full Text Available The purpose of the present study was to determine the impact of different manipulation techniques applied on board fishing vessel, on the microbiological quality of the flesh of European hake (Merluccius merluccius during storage at +3°C ± 1°C for a time (T of 10 days after landing (T1-T10. Samples of fish were taken from a fishing vessel of the Adriatic Sea and from one of the Tyrrhenian Sea, treated on-board under different icing conditions: 1 a low ice/product weight ratio and 2 an optimal ice/product weight ratio, up to 1:3 (3. Spoilage bacteria as Total Bacterial Count (TBC and specific spoilage bacteria as Sulphide Producing Bacteria (SPB were enumerated in fish flesh as Colony Forming Units (CFU/g on Plate Count Agar and Lyngby Agar at 20°C for 3-5 days. TBC of the Adriatic fishes (gutted on-board resulted 103 UFC/g at T1-T6, and 104-105 at T10, whereas TBC of the Tyrrhenian fishes (not gutted on-board resulted 10-102 UFC/g at T2- T3, 103 at T6, and 104-105 at T10. SPB resulted 10- 102 UFC/g at T1-T6, and 103- 104 at T10, with absolute values higher in the Adriatic fishes, in respect with the Tyrrhenian fishes, and in the low icing conditions in respect with the optimal icing condition. At the experimented condition, the lowering of the microbiological quality of fish flesh during storage, seems to be more dependent on the gutting versus not gutting on-board practice rather than on the low versus optimal icing treatment.

Criteria for sustainable fisheries on juveniles illustrated for Mediterranean hake: control the juvenile harvest, and safeguard spawning refugia to rebuild population fecundity

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John F. Caddy

2015-09-01

Full Text Available The paper provides a broad overview of issues relevant to management of fisheries for juvenile fish in contrast to the many stock assessments following Beverton and Holt’s (1957 approach for rational exploitation of mature fishes. A perspective on assessing these fisheries is illustrated for juvenile European hake, Merluccius merluccius, in the northwestern Mediterranean. Here, a constant natural mortality (M assumption is incorrect, as is the assumption that high fecundities are necessarily adequate for stock replacement. The high Ms-at-age for juveniles generated by the reciprocal model are shown to be a logical counterpart to the high fecundity of hake. Charnov’s criterion of intergenerational reproductive replacement is used to test for a sustainable population, analogous to a limit reference point warning of the dangers of overfishing beyond population replacement. Once peak mortality rates of age 2 hake exceed F(2=1.1-1.2, which is currently the case, reproductive replacement may be at risk. Adult exploitation by inshore trawls is low, and maturing hake surviving the fine-mesh trawl fishery migrate offshore with a reduced vulnerability to fine-mesh gears. Early research suggested that rough bottom near the shelf edge once formed a refugium protecting offshore spawners from trawling, and led to abundant recruitment of juveniles nearer shore. It may not do so if offshore fishing effort by reinforced bottom trawls, gill nets and longlines is uncontrolled. Restoring offshore refugia to protect spawners and controlling peak fishing mortality of juveniles would be a precautionary strategy aimed at restoring previous levels of recruitment to the small-mesh trawl fishery.

Fine-scale environmental effects on Cape hake survey catch rates in the Northern Benguela, using data from a trawl-mounted instrument package

DEFF Research Database (Denmark)

Kainge, Paulus Inekela; Wieland, Kai

2017-01-01

We investigated fine-scale effects of environmental variables associated with habitat distribution for 4 size groups of Cape hakes, Merluccius capensis and M. paradoxus, using generalized additive models (GAMs) with a negative binominal error distribution. This study took place during the Namibian...... hake trawl survey of 2016, and was made possible for the first time in Namibia by collecting oceanographic information with a trawl-mounted instrument package concurrently with the catch data. Depth, geographical position, bottom oxygen and bottom temperature had the most pronounced effect on the catch...... rates of both hake species, whereas solar zenith angle representing diel effects and surface layer chlorophyll appeared to be less important. The explained deviance for the best models ranged from 71.4% for M. capensis to 92.7% for M. paradoxus between 43 and 57 cm in length. Differences in catch rates...

Links between the recruitment success of northern European hake (Merluccius merluccius L.) and a regime shift on the NE Atlantic continental shelf

KAUST Repository

Goikoetxea, Nerea; Irigoien, Xabier

2013-01-01

variables in the North Sea also affected the Northeast Atlantic shelf oceanography. Hake recruitment success as well as parameters such as the sea surface temperature, wind patterns and copepod abundance changed significantly at the end of the 1980s

Seasonal and annual variation in Chilean hake Merluccius gayi spawning locations and egg size off central Chile

Science.gov (United States)

Landaeta, Mauricio F.; Castro, Leonardo R.

2012-01-01

Variability in Chilean hake reproductive tactics off central Chile was assessed by analyzing ichthyoplankton samples from nine oceanographic cruises (1996-2005) and through experimental trials with early life stages (eggs, yolk-sac larvae) during the main (austral spring) and secondary (late summer-early autumn) spawning seasons. Abundant eggs in the plankton (1300-2000 eggs per 10 m 2) and historical adult reproductive data showed the highest reproductive activity in austral spring, with large egg aggregations near shelf break (50-100 m depth). Large, recently spawned eggs (1.15-1.20 mm diameter) were advected nearshore by coastward subsurface flows in the spring upwelling season. Experimental trials indicated that recently hatched larvae (3.4-3.5 mm) consumed their yolk-sac (0.17-0.41 mm 3) in 3-4 days at 10-12 °C; plankton sampling indicated that larval hake remained at mid-depth (50-100 m) without showing daily vertical migrations until completing their caudal fin formation (∼15 mm). During the secondary reproductive peak, hake spawned nearshore, when smaller eggs (0.95-1.13 mm) and recently hatched larvae (2.2-2.6 mm notochord length) occurred in surface waters (0-10 m depth). Their relatively large yolk-sac volumes (0.57 ± 0.11 mm 3) provided endogenous nourishment for at least 5 days at 10 °C, according to experiments. In the field, preflexion larvae occurred mainly in the mixed layer (0-25 m) and started ontogenetic daily vertical migrations at 7 mm. A strong decline occurred after 2002 in the adult Chilean hake biomass (estimated by hydroacoustic surveys) and body size, coinciding with variations in spawning locations (more coastward in early spring 2004 and 2005) and decline in egg size. Thus, recent variations in Chilean hake reproductive tactics may reflect an indirect effect of declines in the parental population size.

Four large coastal upwelling areas are created by eastern boundary ...

African Journals Online (AJOL)

spamer

large deep-water hake Merluccius paradoxus, 2.7% small M. paradoxus, 1.3% ... hake in the Benguela region, the shallow-water species. Merluccius capensis .... sharks are not included in the estimate, and neither is the proportion of sharks ...

Pacific Hake Characteristics Affecting the Conduct of an Acoustic Clutter Experiment off the West Coast of the United States

Science.gov (United States)

2012-07-04

Blois , L. C. Hufnagle, A. R. Kronlund, J. A. Holmes, and C. D. Wilson, "The 2003 Integrated Acoustic and Trawl Survey of Pacific Hake, Merluccius...Center, Seattle, WA, 2005. 17. Fleischer, G. W., K. D. Cooke, P. H. Ressler, R. E. Thomas, S. K. de Blois , and L. C. Hufnagle, "The 2005 Integrated...Marine Fisheries Service, Northwest Fisheries Science Center, Seattle, WA, 2008. 18. de Blois , S. K., D. Chu, and K. D. Cooke, "Results of the 2007

Biomass and fishing potential yield of demersal resources from the outer shelf and upper slope of southern Brazil Biomasa y rendimiento potencial pesquero de recursos demersales de la plataforma externa y talud superior del sur de Brasil

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Manuel Haimovici

2009-01-01

Full Text Available The relative abundance and fishing potential of the commercially valuable fishes and cephalopods with marketable size was assessed using two seasonal bottom trawl surveys performed in 2001 and 2002 on the outer shelf and upper slope (100-600 m depth off the coast of southern Brazil. These surveys were part of REVIZEE, a national program designed to assess the fishery potential within the Economic Exclusive Zone. Of the 228 fish and cephalopod species caught during the surveys, only 27 species and genera were considered to be of commercial interest. Commercial-sized individuals of these species made up 52.3% of the total catch. The total biomass was estimated to be 167,193 ton (± 22% and 165,460 ton (± 25% in the winter-spring and summer-autumn surveys, respectively. The most abundant species were the Argentine short-fin squid Illex argentinas, a species with highly variable recruitment, followed by the Argentine hake Merluccius hubbsi, the gulf-hake Urophycis mystacea, and the monkfish Lophius gastrophysus. The latter three were intensively fished prior to the surveys, as well as the beardfish Polymixia lowei and silvery John dory Zenopsis conchifera, both relatively abundant but with a very low market value. The potential yield of the demersal fish species, not considering Illex argentinus, estimated with the Gulland equation for a mean natural mortality of M = 0.31, was 20,460 ton. When considering only Merluccius hubbsi, Urophycis mystacea, and Lophius gastrophysus, the potential yield decreased to 6,625 ton. The surveys showed that the fishery potential of the outer shelf and upper slope was substantially lower than that of the inner shelf. Therefore, this environment should be carefully monitored to avoid overfishing and fast depletion.Se evaluó la abundancia relativa y el potencial pesquero de peces y cefalópodos de especies y tamaños de valor comercial en dos muéstreos estacionales con redes de arrastre de fondo realizados en los a

Anisakid parasites in commercial hake ceviche in southern Chile.

Science.gov (United States)

Torres-Frenzel, Pablo; Torres, Patricio

2014-07-01

The objective of this research was to determine the occurrence of anisakid nematode larvae in hake ceviche sold in restaurants in Valdivia (39°48'S, 73°14'W) and Niebla (39°49'S, 73°22'W), Chile. Between August and November 2012, 78 portions of ceviche were collected (6 from each of the 13 restaurants that sell this product). Each portion was weighed and divided into approximately 30-g samples, which were placed in petri dishes with 0.15 M NaCl. All samples were manually shredded and then examined with a stereomicroscope. Muscles of 41 southern hake (Merluccius australis), a fish sold fresh in Valdivia, also were examined by candling to determine the presence of anisakid larvae. The presence of Pseudoterranova larvae in ceviche sold in Chile was identified for the first time. The pH of ceviche ranges from 4.1 to 4.8, which favors the presence of viable anisakid larvae that tolerate the acid pH similar to that found in the stomach of their mammalian host. No significant differences (P > 0.05) in the prevalence, mean abundance, and mean density of anisakid larvae in ceviche were found between localities. Larvae were detected in ceviche from 3 of 6 restaurants in Valdivia and 4 of 7 restaurants in Niebla. Of the 78 examined portions of ceviche, 21.8% had larvae. The prevalence of viable larvae was 16.7 and 7.1% in the examined portions from Valdivia and Niebla, respectively. In the 41 hake muscle samples from Valdivia, the prevalence (4.9%), mean abundance (0.1), and mean density (0.03) was the same for Pseudoterranova and Anisakis larvae. No inspection processes or pretreatments are currently in place for raw fish to achieve safe conditions for ceviche in restaurants from Valdivia and Niebla.

[IMPACT OF SIX COOKING TECHNIQUES ON FATTY ACID COMPOSITION OF MARLIN (MAKAIRA NIGRICANS) AND HAKE (MERLUCCIUS PRODUCTUS)].

Science.gov (United States)

Castro-González, María Isabel; Carrillo-Domínguez, Silvia

2015-09-01

the regular consumption of fish brings benefits to health due to its content of n-3 fatty acids, but cooking enhances or damages the concentration of fatty acids (FA) since they are susceptible to oxidation by temperatures and cooking times. to analyze the effect of six cooking techniques on total lipids (TL) and (FA) content in marlin and hake and select which one helps the best conservation of health beneficial FA. fillets were subjected to different cooking techniques: steam (ST), foiled-aluminum-paper (FAP), foiled- banana-leaf (FBL), gas-oven (GO), microwave-oven (MO) and fried-lightly (FL). FA were identified by gas chromatography/FID. Marlin: FL increased the concentration of TL and MO decreased it. Statistically, PUFA, SFA and EPA + DHA increased with FAP, MUFA decreased with FBL and increased in FL. Hake: FL increased concentration in all groups of FA while ST decreased it. SFA values and index of atherogenicity (IA), thrombogenicity (IT), peroxidisability and hipocolesterolemic/ hipercolesterolemic fatty acid ratio (HH) found, suggested that hake is a fish with greater health benefits, regardless of the technique you employ. By its EPA + DHA content, marlin seems to be an excellent choice if cooked FAP. FL technique in both species decreased the IA, IT and significantly increased the HH; however n3/n6 ratio decreased. ST seems to be the least desirable cooking technique for both species. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Effects of environmental variables on survey catch rates and distribution by size of shallow- and deep-water Cape hakes, Merluccius capensis and Merluccius paradoxus off Namibia

DEFF Research Database (Denmark)

Kainge, Paulus Inekela; van der Plas, A. K.; Bartholomae, C. H.

2017-01-01

In order to study the effects of temperature, oxygen, salinity and time of day on survey trawl catches, we modeled observed catches of juvenile, small, medium and large hakes per station as functions of zenith angle of the sun, geographical position, year, temperature, salinity, oxygen and depth....

Trawl survey data are applied in fish stock assessment mainly to ...

African Journals Online (AJOL)

denise

Merluccius capensis (shallow-water Cape hake) and. M. paradoxus (deep-water Cape hake) off Namibia provide an ... published data), meaning that the horizontal trawl opening will .... Acoustic data were post-processed twice daily. Hake.

The reproductive biology and the histological and ultrastructural ...

African Journals Online (AJOL)

STORAGESEVER

2010-04-26

Apr 26, 2010 ... characterized by “appearance of isolated follicular epithelial cells around the oocyte and the formation ... Sea. Murua and Motos (2004) studied reproductive biology and histological examination of European hake. (Merluccius merluccius) in the Bay of ... female M. merluccius in the Mediterranean Sea.

SNP Discovery In Marine Fish Species By 454 Sequencing

DEFF Research Database (Denmark)

Panitz, Frank; Nielsen, Rasmus Ory; van Houdt, Jeroen K J

2011-01-01

Based on the 454 Next-Generation-Sequencing technology (Roche) a high throughput screening method was devised in order to generate novel genetic markers (SNPs). SNP discovery was performed for three target species of marine fish: hake (Merluccius merluccius), herring (Clupea harengus) and sole...

Metabarcoding analysis of European hake diet in the Mediterranean Sea

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Giulia Riccioni

2015-10-01

Full Text Available European hake (EH, Merluccius merluccius, is a demersal fish distributed from the North Sea and Atlantic to the Levantine Sea in the Mediterranean. EH is an important predator of deep Mediterranean upper shelf slope communities and it is currently characterised by growth overexploitation. EH adults feed mainly on fish and squids whereas the young (<16 cm feed on crustaceans. All current EH diet studies relied on the morphological identification of prey remains in stomach content, however this method is labour intensive and it precludes the identification of strongly digested food. The development of High-Throughput Sequencing (HTS approaches provide more accurate methods for dietary studies revealing many consumed species simultaneously (DNA metabarcoding. The aim of this study is to use a HTS approach based on COI amplification, contextually to classic microscopic morphological identification, to analyse EH stomach content and to evaluate the efficiency of the molecular method. HTS sequencing has been carried out on the amplicons obtained by PCR amplification (Leray et al. 2013 of stomach remains and all the Miseq Illumina paired-end reads have been analysed by using bioinformatic tools (Boyer et al. 2015 for taxonomic assignment. The selected sequences clustered in OCTUs (Operational Clustered Taxonomic Units and taxonomically assigned, will be used in diversity analyses to compute distance matrices among samples, to compare taxa summaries from different samples, to create networks and perform PCA and PcoA analysis. Classic microscopic morphological analyses on stomach content remains have been carried out contextually to compare the results of the two methods. The molecular approach has proven a promising method to study marine fish dietary habits. All the data will be summarized to reconstruct EH trophic dynamics in the Mediterranean Sea.

The effects of subsampling and between-haul variation on the size-selectivity estimation of Chilean hake (Merluccius gayi gayi Los efectos de submuestreo y variación entre lances en la estimación de la selectividad a la talla de la merluza común (Merluccius gayi gayi

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Dante Queirolo

2012-07-01

Full Text Available Using the data collected in a size selectivity experiment on Chilean hake (Merluccius gayi gayi carried out in 2000, the selectivity parameters for four codend mesh sizes (100, 110, 130, and 140 mm of mesh size opening were estimated and modelled by the SELECT model. These analyses included considerations of the sampling proportions of the catch in the codend and cover. Furthermore, the analyses took into account between-haul variation. The l50 values were 30.8, 29.9, 30.0, and 41.2 cm of total length, respectively, values lower than the estimates obtained from previous studies. The contribution of explanatory variables to the selectivity model was also tested in order to determine the role of mesh size, catch size (in number, and towing speed. Increases in catch size and in towing speed were accompanied by decreases in the l50 estimates. These results demonstrate how incorporation of subsampling effect and explanatory variables to model between-haul variation can improve selectivity estimates and management of a valuable resource.Usando los datos recolectados en un experimento de selectividad a la talla de merluza común (Merluccius gayi gayi realizado en el año 2000, se estimaron y modelaron los parámetros de selectividad para copos de cuatro tamaños de malla (100, 110, 130 y 140 mm de tamaño de malla interno mediante el modelo SELECT. Los análisis incluyeron consideraciones de las proporciones de muestreo de la captura en el copo y en el cubrecopo. Además, los análisis tuvieron en cuenta la variación entre lances. Los valores de l50 fueron 30,8; 29,9; 30,0 y 41,2 cm longitud total respectivamente, valores menores que los obtenidos en estudios previos. Se probó también la contribución de variables explicatorias al modelo de selectividad, para determinar el aporte del tamaño de malla, el volumen de captura (en número y la velocidad de arrastre. Los incrementos en el volumen de captura y en la velocidad de arrastre produjeron una

Evaluation of a class of possible simple interim management ...

African Journals Online (AJOL)

During 1997, considerable scientific differences arose about the status of the Namibian hake (Merluccius capensis and M. paradoxus) resource, and as to whether the hake Total Allowable Catch (TAC) should be substantially decreased or increased. These differences revolved primarily around whether or not abundance ...

Cell and tissue biomarkers in mussel, and histopathology in hake and anchovy from Bay of Biscay after the Prestige oil spill (Monitoring Campaign 2003)

Energy Technology Data Exchange (ETDEWEB)

Marigomez, Ionan [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain)]. E-mail ionan.marigomez@ehu.es; Soto, Manu [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain); Cancio, Ibon [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain); Orbea, Amaia [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain); Garmendia, Larraitz [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain); Cajaraville, Miren P. [Zoologia eta Biologia Zelularra Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea, 644 P.K., E-48080 Bilbo, Basque Country (Spain)

2006-07-01

In order to assess the biological effects of the Prestige oil spill (POS), mussels (Mytilus galloprovincialis), European hake (Merluccius merluccius) and European anchovy (Engraulis encrasicolus) were sampled between April and September 2003 in various geographical areas of Bay of Biscay: Galicia, Central Cantabrian and East Cantabrian. In mussels, several cell and tissue biomarkers were measured: peroxisome proliferation as induction of acyl-CoA oxidase (AOX) activity, lysosomal responses as changes in the structure (lysosomal volume density, V{sub V{sub L}}, surface-to-volume ratio, S/V{sub L}, and numerical density, N{sub V{sub L}}) and in membrane stability (labilization period, LP), cell type replacement as relative proportion of basophilic cells (volume density of basophilic cells, V{sub V{sub BAS}}) in digestive gland epithelium, and changes in the morphology of digestive alveoli as mean luminal radius to mean epithelial thickness (MLR/MET). Additionally, flesh condition index (FCI) and gonad index (GI) were measured as supporting parameters. In hake and anchovy, liver histopathology was examined to determine the prevalence of parasites, melanomacrophage centers, non-specific lesions (inflammatory changes, atrophy, necrosis, apoptosis), early non-neoplastic toxicopathic lesions (i.e., hepatocellular nuclear polymorphism), foci of cellular alteration, benign and malignant neoplasms. In mussels, AOX induction was noticeable in April except in Galicia. LP values were low in all the geographical areas studied, indicating disturbed health, especially in Galicia. Alike, lysosomal enlargement was observed in most stations as shown by the extremely low S/V{sub L} values. V{sub V{sub BAS}} and MLR/MET values were markedly high. Overall, employed biomarkers detected exposure to toxic chemicals and disturbed health in mussels from Bay of Biscay, with impact decreasing from April to September. Although hepatocellular nuclear polymorphism and nematode parasitization in

Alimentación de Squalus acanthias y predación sobre Merluccius hubbsi en el Mar Argentino entre 34°47'-47°S.

OpenAIRE

Garcia de la Rosa, S.B.; Sánchez, M.F.

1997-01-01

The spiny dogfish, Squalus acanthias is an euribatic, euritermic and cosmopolitan specie. In the Argentine Sea it consumes diversity of preys, characteristic of a generalist and oportunist feeder, butits principal food items are ctenophores, fishes and cephalopods.Diet overlap between sexes was found between 34°-37°S and 101-150 m,where males principally feed on fishes, squid and polichaetes,sharing only ctenophores and hake consumption with the females. Near 62 cm TL there is a shift in the ...

BIOSILO DE RESIDUOS DE MERLUZA Y HARINA DE CEBADA FERMENTADOS CON BACTERIAS ÁCIDO LÁCTICAS SELECCIONADAS

Directory of Open Access Journals (Sweden)

EMILIO MARGUET

2017-12-01

Full Text Available Suitability of Lactococcus lactis Tw34 and Lactobacillus plantarum Lb7 as bio-silage inoculants was studied. Experiments were carried out with a mixture of hake (Merluccius hubbsi by-products and barley meal fermented during 7 days. A sample acidified with lactic acid was used as control. In biological mixtures, the pH dropped below 5,0 after 2 days of fermentation and remained stable until the end of the experience. Maximum populations (> 109 CFU/g were reached after 5 days of incubation at 18°C. Water soluble peptides concentration increased during the 7 days of incubation and no significant differences (p 0,05. After 7 days, phosphorous concentrations reached 2.26 and 2,42 g/100 g in bio-silages fermented with Lc. lactis Tw34 and Lb. plantarum Lb7, respectively, while control values remains almost stable (1,61 g/100 g. At the end of the experience, inhibitory activity of trypsin was abolished in both bio-silage while in control sample antinutritional factors remained active. The results indicated the feasibility of the use of the selected mixture as substrate for bio-silage production and the effectiveness Lc. lactis Tw34 and Lb. plantarum Lb7 as inoculants.

The Food and Agriculture Organization, in its Reykjavik Declaration ...

African Journals Online (AJOL)

2005-06-06

Jun 6, 2005 ... information on the geographical distribution of marine species to improve .... snoek, albacore, bigeye tuna, yellowfin tuna, shallow- water Cape hake Merluccius capensis and deep- ..... raw data processing by MCM. Because ...

lutionary research has been on the relationships and structure of ...

African Journals Online (AJOL)

denise

off Namibia have been limited by either a spatial or a temporal scale ... Antarctic Intermediate, deep and bottom waters. (Shannon .... either to include or to ignore rare species (Alatalo ...... Shallow-water Cape hake Merluccius capensis, horse.

Hake Survey ADCP (2005)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Shipboard acoustic Doppler current profiler data collected during the Integrated Acoustic and Trawl Surveys of Pacific Hake. Processing by: Stephen Pierce, Oregon...

Hake Survey ADCP (1998)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Shipboard acoustic Doppler current profiler data collected during the Integrated Acoustic and Trawl Surveys of Pacific Hake. Processing by: Stephen Pierce, Oregon...

Hake Survey ADCP (1995)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Shipboard acoustic Doppler current profiler data collected during the Integrated Acoustic and Trawl Surveys of Pacific Hake. Processing by: Stephen Pierce, Oregon...

Hake Survey ADCP (2001)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Shipboard acoustic Doppler current profiler data collected during the Integrated Acoustic and Trawl Surveys of Pacific Hake. Processing by: Stephen Pierce, Oregon...

Hake Survey ADCP (2003)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Shipboard acoustic Doppler current profiler data collected during the Integrated Acoustic and Trawl Surveys of Pacific Hake. Processing by: Stephen Pierce, Oregon...

The Benguela upwelling system is one of the most productive in the ...

African Journals Online (AJOL)

spamer

Waldron and Probyn 1992), providing a large biomass of plankton and planktivo- rous fish (Ware 1992) that in turn are preyed on by the. Cape hakes Merluccius capensis and M. paradoxus, which are dominant and highly successful demersal.

By-catch composition of the Patagonian scallop fishery: the fishes Composición de la captura incidental en la pesquería de vieira patagónica: los peces

Directory of Open Access Journals (Sweden)

Laura Schejter

2012-11-01

Full Text Available An inventory of 24 fish species incidentally caught by the Patagonian scallop fleet in the SW Atlantic Ocean is provided for the first time. The most frequent species were Psammobatis spp. (81.4%, Bathyraja brachyurops (75.1%, B. macloviana (73.5%, Patagonotothen ramsayi (66.1%, Merluccius hubbsi (53.7% and B. albomaculata (50.3%. Many of the recorded chondrichthyes are considered vulnerable or endangered species. The number of taxa (fishes + invertebrates that conforms the by-catch of the fishery was increased and updated to nearly 200 species.Este estudio presenta por primera vez un inventario con 24 especies de peces registradas en la captura incidental de la pesca de la vieira patagónica en el Océano Atlántico sudoccidental por la flota pesquera comercial. Las especies más frecuentes fueron Psammobatis spp. (81,4%, Bathyraja brachyurops (75,1%, B. macloviana (73,5%, Patagonotothen ramsayi (66,1%, Merluccius hubbsi (53,7% y B. albomaculata (50,3%. Muchos de los condrictios registrados se encuentran actualmente considerados como especies vulnerables o en peligro. El número de taxa (peces + invertebrados que conforman la captura incidental de esta pesquería se incrementó y actualizó con estos resultados a aproximadamente 200 especies.

Increasingly, holistic ecosystem approaches are being developed ...

African Journals Online (AJOL)

were investigated by means of a posteori tests. Cumulative prey ... mum 12 h) or frozen for later processing ashore. Gonads were ..... (e.g. sardine, round herring), or prefer deeper offshore waters (e.g. .... Cape hake (shallow-water). Merluccius ...

Aspects of the reproductive biology of monkfish Lophius vomerinus ...

African Journals Online (AJOL)

Aspects of the reproductive biology of monkfish Lophius vomerinus are described from material collected during hake Merluccius spp. biomass surveys and from commercial monkfish and sole Austroglossus microlepis vessels between January 1996 and June 2000 off Namibia at depths between 97m and 686m.

A history of recent bases for management and the development of a ...

African Journals Online (AJOL)

The bases for historical catch limits placed on the hake fishery are reviewed in brief for ... Management Procedure (OMP) approach was introduced for this fishery. ... species-disaggregated assessments of the resource as Operating Models. ... (substantial Merluccius paradoxus and catch per unit effort [CPUE] recovery, and ...

The Cape commercial linefishery consists of about 2 500 vessels ...

African Journals Online (AJOL)

spamer

assessing the ecosystem effects of fishing and evaluating the benefits of ... Such information would assist in the ... Traditional Cape linefish may be broadly divided into ... gressively farther offshore (and into deeper. Griffiths: ... (Griffiths 1997c); this process controls avail- ... of shallow-water Cape hake Merluccius capensis,.

Incidence and significance of cystic structures in the ovaries of gadoid fish

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Rosario Domínguez-Petit

2011-06-01

Full Text Available Fish regulate egg production by atresia. Sometimes, oocytes are encapsulated in cystic structures that might remain in the ovary for months, altering female reproductive potential in future spawning seasons. Ovaries of Atlantic cod (Gadus morhua, L. from the Flemish Cap and European hake (Merluccius merluccius, L. from the Galician Shelf (NW Spain were analysed from 1999 to 2006. The prevalence and abundance of ovarian cysts were estimated. Cyst prevalence increased with female size and/or age for both species, and decreased with high condition factor in hake. Cyst intensity does not correlate with any analysed factor. The size/age structure of spawning stock biomass and female condition could affect the prevalence of cysts in the ovaries, though it does not seem to affect cyst intensity in the ovary. Further research is needed to determine cyst resorption time and the impact that it has on egg production and consequently on stock reproductive potential.

Bayesian analysis of allozyme markers indicates a single genetic ...

African Journals Online (AJOL)

Kingklip Genypterus capensis inhabit deep continental shelf and slope waters off southern Africa and are now largely harvested as a bycatch in trawl and longline fisheries for Cape hakes Merluccius spp. Regional differences in growth, vertebral count and otolith morphology indicate that kingklip may consist of three stocks.

A model of trophic flows in the northern Benguela upwelling system ...

African Journals Online (AJOL)

Ultimately, this type of model may form a basis for multispecies management approaches in the region. By the 1980s, sardine Sardinops sagax and hake Merluccius spp. stocks in the northern Benguela had both undergone a decline, yet were still heavily fished. Horse mackerel Trachurus trachurus capensis had increased ...

Spawning strategies and transport of early stages of the two Cape ...

African Journals Online (AJOL)

Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs and larvae of Merluccius paradoxus and M. capensis ...

Trophic ecology of yellownose skate Zearaja chilensis, a top predator in the south-western Atlantic Ocean.

Science.gov (United States)

Belleggia, M; Andrada, N; Paglieri, S; Cortés, F; Massa, A M; Figueroa, D E; Bremec, C

2016-03-01

The diet and trophic level (TL ) of the yellownose skate Zearaja chilensis in the south-western Atlantic Ocean (35°-54° S), and how these varied in relation to body size, sex, maturity stage, depth and region were determined by analysis of stomach contents. From 776 specimens analysed, 671 (86·5%) ranging from 180 to 1190 mm total length (LT ) had prey in their stomachs. The diet was dominated by fishes, mainly the notothenioid Patagonotothen ramsayi and the Argentine hake Merluccius hubbsi. The consumption of fishes and crabs increased with increasing predator size, and these preys were more important in the north than in the south. Isopods and other crustaceans were consumed more in the south and their consumption decreased as the size of Z. chilensis increased. The TL of Z. chilensis increased with LT from 4·29 to 4·59 (mean 4·53), confirming their ecological role as a top predator. The small and large size classes exhibited a low diet overlap and the highest spatial segregation, whereas medium and large specimens had higher co-occurrence and dietary overlap indices. A clear distinction in tooth shape was noted between sexes in adult specimens, with males having longer cusps. This sexual heterodonty may be related to reproductive behaviour, increasing the grasping ability of males during courtship, because there were no differences in diet between the sexes. © 2016 The Fisheries Society of the British Isles.

New Fisheries-related data from the Mediterranean Sea (November, 2016

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A. ANASTASOPOULOU

2016-11-01

Full Text Available In this fourth Collective Article, with fisheries-related data from the Mediterranean, we present weight-length relationships for eight deep-sea fish species (Brama brama, Conger conger, Etmopterus spinax, Molva macrophthalma, Mora moro, Pagellus bogaraveo, Phycis blennoides from the Eastern Ionian Sea; Scyliorhinus canicula from various locations in the Mediterranean Sea and weight-length relationships and condition factor of five Mugilidae species (Liza aurata, Liza saliens, Liza ramada, Mugil cephalus, Chelon labrosus from a Mediterranean lagoon in the Ionian Sea. Moreover, we present otolith weight, fish length and otolith length relationships of the red mullet (Mullus barbatus in the Aegean and Ionian Sea and otolith weight relationships in European hake (Merluccius merluccius from the Greek Seas.

Growth models fitted to Dipturus chilensis length-at-age-data support a two phase growth Modelos de crecimiento ajustados a datos de largo a la edad de Dipturus chilensis confirman un crecimiento en dos fases

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MARINA I AVERSA

2011-03-01

Full Text Available Age and growth for the beaked skate was estimated from bands in the vertebral centra of 689 individuals obtained from incidental catches of the Argentine hake (Merluccius hubbsi fishery. Age bias plots and indices of precision indicated that ageing method was precise and unbiased (% CV = 3 % PA = 82.09 %. Edge and marginal increment analysis of the vertebrae support the hypothesis of annual band pair deposition. Three growth models were fitted to length-at-age and the two-phase growth model produced the best fit. This feature has never been described before for D. chilensis and can be related to changes in energy allocation and the shift from juvenile to adult phase. The unrealistic biological estimates of the von Bertalanffy growth model illustrates the importance of fitting alternative models to the data. Female beaked skates reached greater size in length (L∝ as well as in disc width (L∝ = 138.2 cm; DW∝ = 92.46 cm and have lower growth rate (k = 0.08 yr-1 than males (L∝ = 106.7 cm; DW∝ = 74.52 cm; k = 0.121 yr-1. This study provides basic information on age and growth for the beaked skate, D. chilensis, which were previously not available for its south Atlantic range of distribution.La edad y el crecimiento de la raya picuda fue estimado a partir de las bandas en los cuerpos vertebrales de 689 individuos obtenidos de las capturas incidentales de la pesquería de merluza argentina (Merluccius hubbsi. Gráficos de sesgos y el análisis de precisión indicaron que el método utilizado para la determinación de la edad es preciso y no sesgado (% CV = 3 % PA = 82.09 %. El análisis del tipo de borde e incremento marginal vertebral confirmó la hipótesis del depósito anual de un par de bandas. Se ajustaron tres modelos de crecimiento a los datos de largo a la edad y el modelo de dos fases produjo el mejor ajuste. Esta característica nunca antes fue descripta para Dipturus chilensis y podría relacionarse con un cambio en la cuota de

There are two commercially exploited species of hake off Namibia ...

African Journals Online (AJOL)

denise

on average 93% of the total landings of hake between. 1991 and ..... virtual population analysis (VPA) to formulate man- agement ... the same species below optimum levels, allowing the stock to .... 2001 — Depth-stratified density estimates.

The behavior of hake prices in Chile: is the world market leading?

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Felipe Quezada

2014-11-01

Full Text Available In this study we analyzed price determination throughout the Chilean hake market chain. To analyze the relationship between different prices participating in this chain, a VECM model was successfully estimated. One cointegration vector was identified. Tests for weak exogenous variables, causality, and significance of different variables were performed, and a parsimonious version of the model was selected. The results obtained in this paper outline a price determination process that, in the end, is governed by world market conditions. Moreover, the diverse links in the hake market chain seem to be well integrated, which implies that there is little room for domestic price determination.

Deep-water fisheries in Brazil: history, status and perspectives Pesquerías de aguas profundas en Brasil: historia, situación actual y perspectivas

Directory of Open Access Journals (Sweden)

José Angel Alvarez Perez

2009-01-01

Full Text Available The recent development of deep-water fisheries off Brazil is reviewed from biological, eco-nomic, and political perspectives. This process has been centered in the southeastem and southern sectors of the Brazilian coast (19°-34°S and was motivated by the overfishing of the main coastal resources and a government-induced vessel-chartering program. Shelf break (100-250 m operations by national hook-and-line and trawl vessels intensified in the 1990s. Around 2000-2001, however, foreign-chartered longliners, gillnetters, potters, and trawlers started to operate in Brazilian waters, leading the occupation of the upper slope (250-500 m, mostly targeting monkfish (Lophyus gastrophysus, the Argentine hake (Merluccius hubbsi, the Brazilian codling (Urophycis mystacea, the wreckfish (Polyprion americanus, the Argentine short-fin squid (Illex argentinus, the red crab (Chaceon notialis, and the royal crab (Chaceon ramosae. Between 2004 and 2007, chartered trawlers established a valuable fishery on deep-water shrimps (family Aristeidae, heavily exploiting the lower slope (500-1000 m. Total catches of deep-water resources varied annually from 5,756 ton in 2000 to a maximum of 19,923 ton in 2002, decreasing to nearly 11,000 ton in 2006. Despite intensive data collection, the availability of timely stock assessments, and a formal participatory process for the discussion of management plans, deep-water stocks are already considered to be overexploited due to limitations of governance. .El reciente desarrollo de la pesca profunda en Brasil fue revisado desde perspectivas biológicas, econômicas y políticas. Este proceso se ha centrado en los sectores sureste y sur de la costa de Brasil (19°-34°S y fue motivado por la sobrepesca de los principales recursos costeros en conjunto con una política gubernamental de arriendo de buques pesqueros. Las operaciones de pesca sobre el borde de la plataforma (100-250 m por buques palangreros y arrastreros se

Cape hake Merluccius capensis are abundant over the Namibian ...

African Journals Online (AJOL)

spamer

In summer 1994, oxygen depletion was very pro- nounced in bottom waters over the Namibian shelf, from 18 to 25°S. In January, bottom water of the inner and midshelf regions of northern and central Namibia was depleted of oxygen to levels as low as <0.5 ml.l–1, with levels of between 1 and 2 ml.l–1 at the shelf edge.

The diurnal vertical dynamics of cape hake and their potential prey ...

African Journals Online (AJOL)

cephalopods. Together with their cohabitant potential prey, hake are known to undertake diurnal vertical migrations, aggregating near the bottom during daylight, but migrating off the bottom at night. An attempt to determine the ... predation dominating. This may indicate a feeding strategy where vision is not important.

Influence of tow duration on catch performance of trawl survey in the Mediterranean Sea.

Directory of Open Access Journals (Sweden)

Antonello Sala

Full Text Available The aim of this study was to assess the effect of tow duration on catch per unit of swept area (CPUE, trawl catch performance, and the proportion of the species caught in a trawl survey. Longer tows are expected to have a greater probability of catching species. An average of 26 species were caught in the first 30 minutes, whereas only about one additional species was caught in the next 30 minutes in longer tows. The shorter tows involved a decrement in catch weight for 11 of the 12 target species sampled, demonstrating that tow duration did affect catch per unit of swept area CPUE. The shorter tows were associated with a significant reduction of the overall CPUE in terms of weight of the main target species and of the total catch (circa 60%. The same strong reduction of around 70% was found in particular for European hake (Merluccius merluccius and surmullet (Mullus spp and 50% for Nephrops (Nephrops norvegicus. The shorter tows were less efficient in catching large-sized hake, surmullet, Nephrops, Atlantic horse mackerel (Trachurus trachurus, and poor cod (Trisopterus minutus, even though the difference was significant only for Nephrops. Regardless of the p-value statistic, these findings suggest that the continuity of survey time series would be severely impaired by changing tow duration. Further work is required to explore a way to reduce tow duration without reducing CPUE.

Diet of bottlenose dolphins (Tursiops truncatus from the Gulf of Cadiz: Insights from stomach content and stable isotope analyses.

Directory of Open Access Journals (Sweden)

Joan Giménez

Full Text Available The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin (Tursiops truncatus, which exhibits a highly varied diet throughout its distribution range. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems, as well as its interaction with important ecosystem services such as fisheries. Here, we combined stomach content analyses (SCA and stable isotope analyses (SIA to describe bottlenose dolphins diet in the Gulf of Cadiz (North Atlantic Ocean. Prey items identified using SCA included European conger (Conger conger and European hake (Merluccius merluccius as the most important ingested prey. However, mass-balance isotopic mixing model (MixSIAR, using δ13C and δ15N, indicated that the assimilated diet consisted mainly on Sparidae species (e.g. seabream, Diplodus annularis and D. bellottii, rubberlip grunt, Plectorhinchus mediterraneus, and common pandora, Pagellus erythrinus and a mixture of other species including European hake, mackerels (Scomber colias, S. japonicus and S. scombrus, European conger, red bandfish (Cepola macrophthalma and European pilchard (Sardina pilchardus. These contrasting results highlight differences in the temporal and taxonomic resolution of each approach, but also point to potential differences between ingested (SCA and assimilated (SIA diets. Both approaches provide different insights, e.g. determination of consumed fish biomass for the management of fish stocks (SCA or identification of important assimilated prey species to the consumer (SIA.

Juvenile hake predation on Myctophidae and Sternoptychidae: Quantifying an energy transfer between mesopelagic and neritic communities

Science.gov (United States)

Modica, Larissa; Cartes, Joan E.; Velasco, Francisco; Bozzano, Anna

2015-01-01

Seasonal study of the diet and food consumption of juvenile hake has been carried out in the Central Mediterranean Sea (Southern Tyrrhenian Sea). Fish were the most important food resource in terms of weight (ca. 70%). Among the fish, Myctophidae and Sternoptychidae, which are usually distributed deeper than juvenile hake, are most important. During summer, Ceratoscopelus maderensis constituted up to 21% of weight of all prey, and Maurolicus muelleri represented almost 10%. During autumn M. muelleri became the most important food resource. The way in which these more deeply distributed prey enter shallower food webs relates to the daily vertical migrations of lanternfish. In upper water column strata at night or near dawn they become prey of the juvenile hake. Considering that trophic energy flows primarily downward, in the direction of the productivity gradient, the observed flow of energy from deep strata into epipelagic layers could be considered an inverse energy transfer. Daily food consumption of juvenile hake ranged between 4.11 and 4.72% of the body wet-weight (BWW). The application of a square-root model allowed calculation of the fraction of this consumption derived by ingestion of the more deeply distributed mesopelagic fish. Between 11.6% and 17.8% of food consumption was sustained by this energy flow. Such information is useful for understanding the interaction between communities distributed in different depth ranges and to reinforce the idea that marine communities are open systems in which migratory movements can dramatically change the assumptions and results of mass-balance models.

Oceanographic data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

Biological data - Integrated acoustic and trawl survey of Pacific hake off the Pacific Coast

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Integrated acoustic and trawl surveys are used to assess the distribution, biomass, and biology of Pacific hake along the Pacific coasts of the United States and...

Gamma radiation effects with Co-60 for radurization and radicidation in fillets and fish eggs of the Merluccius Merluccius hubbsi

International Nuclear Information System (INIS)

Valdes Rodriguez, E

1982-01-01

Part I: theoretical considerations: introduction, methodology in the processing of foods, physical-chemical action of the radiations, microbiologycal aspects, action of the radiation and of the drops temperatures, physiologic aspects, changes taken place in the stored fish, changes taken place by the ionizing radiation in the biological structures. II: Experimental work, generalities of experimental work, objectives, materials and methods of the experimental work, presentation of results, conclusions

Negative binomial distribution to describe the presence of Trifur tortuosus (Crustacea: Copepoda in Merluccius gayi (Osteichthyes: Gadiformes

Directory of Open Access Journals (Sweden)

Giselle Garcia-Sepulveda

2017-06-01

Full Text Available This paper describes the frequency and number of Trifur tortuosus in the skin of Merluccius gayi, an important economic resource in Chile. Analysis of a spatial distribution model indicated that the parasites tended to cluster. Variations in the number of parasites per host can be described by a negative binomial distribution. The maximum number of parasites observed per host was one, similar patterns was described for other parasites in Chilean marine fishes.

Evolution of male coloration during a post-Pleistocene radiation of Bahamas mosquitofish (Gambusia hubbsi).

Science.gov (United States)

Martin, Ryan A; Riesch, Rüdiger; Heinen-Kay, Justa L; Langerhans, R Brian

2014-02-01

Sexual signal evolution can be complex because multiple factors influence the production, transmission, and reception of sexual signals, as well as receivers' responses to them. To grasp the relative importance of these factors in generating signal diversity, we must simultaneously investigate multiple selective agents and signaling traits within a natural system. We use the model system of the radiation of Bahamas mosquitofish (Gambusia hubbsi) inhabiting blue holes to test the effects of resource availability, male body size and other life-history traits, key aspects of the transmission environment, sex ratio, and predation risk on variation in multiple male color traits. Consistent with previous work examining other traits in this system, several color traits have repeatedly diverged between predation regimes, exhibiting greater elaboration in the absence of predators. However, other factors proved influential as well, with variation in resource levels, body size, relative testes size, and background water color being especially important for several color traits. For one prominent signaling trait, orange dorsal fins, we further confirmed a genetic basis underlying population differences using a laboratory common-garden experiment. We illustrate a promising approach for gaining a detailed understanding of the many contributing factors in the evolution of multivariate sexual signals. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

Changes in the protein fraction of Merluccius bilinearis muscle under lactic acid bacterial fermentation using a Lactobacillus Acidophilus starter culture (ESP)

OpenAIRE

Elizondo, Luis J.

2016-01-01

The effect of lactic acid bacterial fermentation on the protein fraction of Merluccius bilinearis muscle was evaluated. The non-protein fraction increased progressively with corresponding decreases in the percentage protein (dry weight) indicating proteolytic activity during fermentation. Significant increases in the percentages of the amino acids cystine, isoleucine, phenylalanine and tyrosine were observed after two months of fermentation. Percentages of arginine decreased significantly aft...

Environmental eff ects on the availability of shallow and deep-water hake to the demersaltrawl survey in Namibian waters

DEFF Research Database (Denmark)

Kainge, Paulus Inekela

at different size groups (juvenile, small, medium and large) of the two hake species. Most of the years, the environmental data were collected independent of the fishing operations usually on few selected transects with limited spatial overlap between the CTD and the trawl stations. The results, however...

Testing Nordmøre grids on the target and by-catch species of the commercial bottom trawl fishery in the Gulf of Cadiz

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Mariángeles Gamaza

2015-12-01

Full Text Available Sorting grids have been tested worldwide in trawl fisheries. Here we report upon the first trials performed using Nordmøre sorting grids with four different bar spacings in the trawl fisheries of the Gulf of Cadiz targeting crustaceans as the main resource. A total of 288 valid hauls and 67 commercial species were caught. Escapement and escape size selectivity were evaluated for the most important target and by-catch species. A decrease in the percentage of biomass escape was recorded with increasing grid spacing for the two target species, deep-water rose shrimp (Parapenaeus longirostris and Norway lobster (Nephrops norvegicus, from 24% to 8% for the former and from 86 to 9% for the latter, with a 15-mm and 30-mm grid respectively. In general, high escape rates were found for most finfish and cephalopods. For hake (Merluccius merluccius, as the main by-catch species, the results showed an escape rate decreasing from 96% to 71% as the bar spacing increased. Our findings suggest the 30-mm grid would be effective for the deep-water crustacean trawlers but different mitigation measures will be required for other métiers in the multispecies trawl fishery of the Gulf of Cadiz.

Bycatch of crustacean and fish bottom trawl fisheries from southern Portugal (Algarve

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Maria Esmeralda Costa

2008-12-01

Full Text Available As part of two research projects for analysing bycatch and discards, we quantified catch composition, catch rates, bycatch and discards in two important commercial bottom trawl fisheries (crustacean and fish trawls off the southern coast of Portugal (Algarve. Stratified sampling by onboard observers took place from February 1999 to March 2001 and data were collected from 165 tows during 52 fishing trips. Commercial target species included crustaceans: blue and red shrimp (Aristeus antennatus, deep-water rose shrimp (Parapenaeus longirostris, Norway lobster (Nephrops norvegicus; and fishes: seabreams (Diplodus spp. and Pagellus spp., horse mackerels (Trachurus spp. and European hake (Merluccius merluccius. The trawl fisheries are characterised by considerable amounts of bycatch: 59.5% and 80.4% of the overall total catch for crustacean and fish trawlers respectively. A total of 255 species were identified, which belonged to 15 classes of organisms (137 vertebrates, 112 invertebrates and 6 algae. Crustacean trawlers had higher bycatch biodiversity. Bony fish (45.6% and 37.8% followed by crustaceans (14.6% and 11.5% were the dominant bycatch components of both crustacean and fish trawlers respectively. The influence of a number of factors (e.g. depth, fishing gear, tow duration and season on bycatch and discards is discussed.

Determination of essential and toxic elements in sea bass (Centropomus sp.) and hake (Cynoscion leiarchus) consumed in the city of Sao Paulo by neutron activation analysis

International Nuclear Information System (INIS)

Fabiano, Karen C.; Moreira, Edson G.; Vasconcellos, Marina B.A.

2013-01-01

The goal was to use the Instrumental Neutron Activation Analysis (INAA) to evaluate the levels of essential and toxic elements in samples of hake (Cynoscion leiarchus) and sea bass (Centropomus sp.) that are most consumed fish in the town of some Sao Paulo. Ten specimens of hake and sea bass were acquired in Companhia de Entrepostos e Armazens Gerais de Sao Paulo (CEAGESP), main supply center for the population of the metropolitan area of Sao Paulo. After gutted and cleaned, the edible tissue was freeze-dried, ground and sieved. The elements were determined through the use of hyperpure germanium spectrometer after irradiation in the nuclear research reactor IEAR-1

What can gene flow and recruitment dynamics tell us about connectivity between European hake stocks in the Eastern North Atlantic?

Science.gov (United States)

Pita, Alfonso; Pérez, Montse; Cerviño, Santiago; Presa, Pablo

2011-04-01

Systematic genetic analyses of fish populations allow the testing of temporal stability in their genetic structures and better understanding their pattern of connectivity. In this study the pattern of gene flow between the two Atlantic stocks of the European hake has been examined for the period 2000-2002. Present analyses indicate that a large genetic homogeneity existed among all Atlantic populations in that period, and that a systematic grouping occurred between Porcupine Bank samples and Cantabric ones. This scenario is congruent with an inter-annual gene flow from central grounds of the northern stock (Porcupine and Great Sole) to Iberian grounds inhabited by the southern stock. Additionally, estimated migration figures were in agreement with the good recruitments observed in the southern stock after 2003 despite the spawning biomass was at its historical minimum. Altogether these results highlight the central role of Porcupine bank and Great Sole in making sustainable both stocks and advocate the integrative management of this hake fishery by means of a multidisciplinary assessment.

Changes in the protein fraction of Merluccius bilinearis muscle under lactic acid bacterial fermentation using a Lactobacillus Acidophilus starter culture (ESP

Directory of Open Access Journals (Sweden)

Luis J. Elizondo

2016-03-01

Full Text Available The effect of lactic acid bacterial fermentation on the protein fraction of Merluccius bilinearis muscle was evaluated. The non-protein fraction increased progressively with corresponding decreases in the percentage protein (dry weight indicating proteolytic activity during fermentation. Significant increases in the percentages of the amino acids cystine, isoleucine, phenylalanine and tyrosine were observed after two months of fermentation. Percentages of arginine decreased significantly after one week and again after two months of fermentation.

Protein gels and emulsions from mixtures of Cape hake and pea proteins.

Science.gov (United States)

Tomé, Ana Sofia; Pires, Carla; Batista, Irineu; Sousa, Isabel; Raymundo, Anabela

2015-01-01

Portioning of frozen fish generates by-products such as fish 'sawdust' and cut-offs which can be further processed into protein concentrates and isolates. The objective of the present work was to produce gels and emulsions using recovered Cape hake protein powder (HPP). In previous works, the structures of the gels produced by HPP were found to be strong, with a high rubbery character. In this work, the addition of commercial pea proteins (PPC) to HPP gels and emulsions was studied. Physical properties of gels and emulsions prepared with different proportions of mixtures of PPC and HPP were evaluated. In general, gels and emulsions showed high values for whiteness and, as expected, the higher content of HPP in the protein mixtures led to higher firmness values of the gels. The gel network was rapidly formed upon heating due to the fish protein macromolecules and further reinforced by the pea protein macromolecules when cooled to 5 °C. Both visco-elastic parameters, storage and loss moduli, of the produced gels increased with the HPP proportion in the protein mixtures, corresponding to more structured systems. For the emulsions, two different pH environments were studied: 3.8 and 7.0. At neutral pH a synergy was found between the vegetable and fish protein, which is not so strong when pH is lowered to 3.8, near the isoelectric point of pea proteins (pI = 4.5). This evidence was supported by the results from the texture measurements, viscosity and visco-elastic parameters. Gels made from Cape hake proteins showed a softer texture and were less rubbery with the addition of pea proteins. Emulsions stabilised by these mixtures showed slightly different behaviour when produced at pH 7.0 or pH 3.8. © 2014 Society of Chemical Industry.

Variation in wind and piscivorous predator fields affecting the survival of Atlantic salmon, Salmo salar, in the Gulf of Maine

Science.gov (United States)

Friedland, K.D.; Manning, J.P.; Link, Jason S.; Gilbert, J.R.; Gilbert, A.T.; O'Connell, A.F.

2012-01-01

Observations relevant to the North American stock complex of Atlantic salmon, Salmo salar L., suggest that marine mortality is influenced by variation in predation pressure affecting post-smolts during the first months at sea. This hypothesis was tested for Gulf of Maine (GOM) stocks by examining wind pseudostress and the distribution of piscivorous predator fields potentially affecting post-smolts. Marine survival has declined over recent decades with a change in the direction of spring winds, which is likely extending the migration of post-smolts by favouring routes using the western GOM. In addition to changes in spring wind patterns, higher spring sea surface temperatures have been associated with shifting distributions of a range of fish species. The abundance of several pelagic piscivores, which based on their feeding habits may predate on salmon post-smolts, has increased in the areas that serve as migration corridors for post-smolts. In particular, populations of silver hake, Merluccius bilinearis (Mitchell), red hake, Urophycis chuss (Walbaum), and spiny dogfish, Squalus acanthias L., increased in size in the portion of the GOM used by post-smolts. Climate variation and shifting predator distributions in the GOM are consistent with the predator hypothesis of recruitment control suggested for the stock complex.

Otter trawls in Greece: Landing profiles and potential mιtiers

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S. KATSANEVAKIS

2010-02-01

Full Text Available A fleet of 326 bottom trawlers operate in Greek Seas and their landings represent approximately 30% of the total fish production in Greece. In this study, otter trawl landings data were analyzed in order to identify potential métiers. Landings data between 2002 and 2006 were used, collected from 42 ports in the Aegean and East Ionian Sea. A three-step procedure was applied to identify potential métiers: the first step involved a factorial analysis of the log-transformed landings profiles, the second step a classification of the factorial coordinates, and the third step a further aggregation of clusters based on expert knowledge. In all, six potential métiers were identified in the Aegean Sea, and five in the Ionian Sea. The most important target species were European hake (Merluccius merluccius, deepwater pink shrimp (Parapenaeus longirostris, red mullet (Mullus barbatus, caramote prawn (Melicertus kerathurus, picarel (Spicara smaris, cephalopods, bogue (Boops boops, anglers (Lophiusspp., and Norway lobster (Nephrops norvegicus. Otter trawls in Greece use more or less the same gear with minor modification, and métier selection is basically reflected as a choice of geographical sub-area and hauling depth. The limitations of using landings profiles to identify métiers and the need for further verification are discussed.

Hake fish bone as a calcium source for efficient bone mineralization.

Science.gov (United States)

Flammini, Lisa; Martuzzi, Francesca; Vivo, Valentina; Ghirri, Alessia; Salomi, Enrico; Bignetti, Enrico; Barocelli, Elisabetta

2016-01-01

Calcium is recognized as an essential nutritional factor for bone health. An adequate intake is important to achieve or maintain optimal bone mass in particular during growth and old age. The aim of the present study was to evaluate the efficiency of hake fish bone (HBF) as a calcium source for bone mineralization: in vitro on osteosarcoma SaOS-2 cells, cultured in Ca-free osteogenic medium (OM) and in vivo on young growing rats fed a low-calcium diet. Lithotame (L), a Ca supplement derived from Lithothamnium calcareum, was used as control. In vitro experiments showed that HBF supplementation provided bone mineralization similar to standard OM, whereas L supplementation showed lower activity. In vivo low-Ca HBF-added and L-added diet similarly affected bone deposition. Physico-chemical parameters concerning bone mineralization, such as femur breaking force, tibia density and calcium/phosphorus mineral content, had beneficial effects from both Ca supplementations, in the absence of any evident adverse effect. We conclude HBF derived from by-product from the fish industry is a good calcium supplier with comparable efficacy to L.

Behaviour of fish by-catch in the mouth of a crustacean trawl.

Science.gov (United States)

Queirolo, D; Gaete, E; Montenegro, I; Soriguer, M C; Erzini, K

2012-06-01

The behaviour of fish by-catch was recorded and characterized by in situ observations in the mouth of a crustacean trawl using an underwater camera system with artificial light, at depths between 106 and 461 m, along the central coast of Chile. The groups or species studied were rattails (family Macrouridae), Chilean hake Merluccius gayi gayi, sharks (orders Carcharhiniformes and Squaliformes), skates (family Rajidae), flatfishes (genus Hippoglossina) and small benthopelagic and demersal fishes (orders Osmeriformes, Stomiiformes, Gadiformes, Ophidiiformes and Perciformes). The fish behaviour was categorized in terms of (1) position in the water column, (2) initial orientation with respect to the trawl, (3) locomotion and (4) swimming speed with respect to the trawl. Rattails, sharks, skates and flatfishes were passive in response to the trawl and showed similar behavioural patterns, with most fishes observed sitting or touching the bottom with no swimming or other activity. Merluccius gayi gayi was the most active species, displaying a wide combination of behavioural responses when the trawl approached. This species showed several behavioural patterns, mainly characterized by swimming forward at variable speed. A fraction of small bentho-pelagic and demersal fishes also showed an active behaviour but always at lower speed than the trawl. The species-specific differences in behaviour in the mouth of the trawl suggest that improvements at the level of the footrope can be made to reduce by-catch, especially of passive species. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Determination of the Geographical Origin of All Commercial Hake Species by Stable Isotope Ratio (SIR) Analysis.

Science.gov (United States)

Carrera, Mónica; Gallardo, José M

2017-02-08

The determination of the geographical origin of food products is relevant to comply with the legal regulations of traceability, to avoid food fraud, and to guarantee food quality and safety to the consumers. For these reasons, stable isotope ratio (SIR) analysis using an isotope ratio mass spectrometry (IRMS) instrument is one of the most useful techniques for evaluating food traceability and authenticity. The present study was aimed to determine, for the first time, the geographical origin for all commercial fish species belonging to the Merlucciidae family using SIR analysis of carbon (δ 13 C) and nitrogen (δ 15 N). The specific results enabled their clear classification according to the FAO (Food and Agriculture Organization of the United Nations) fishing areas, latitude, and geographical origin in the following six different clusters: European, North African, South African, North American, South American, and Australian hake species.

Efecto del uso de paneles de escape de malla cuadrada sobre la reducción de peces juveniles en la pesquería de arrastre de merluza común (Merluccius gayi gayi Effect of the use of square mesh escape panels on the reduction of young fish in the common hake (Merluccius gayi gayi trawl fishery

Directory of Open Access Journals (Sweden)

Dante Queirolo

2008-01-01

Full Text Available La evaluación de paneles de escape de malla cuadrada en redes de arrastre de fondo usadas en la pesquería de merluza común se realizó empleando dos metodologías complementarias: lances con sobrecopo y lances alternados. Los lances con sobrecopo permitieron cuantificar la fracción de la captura que escapa a través de los paneles de escape, y determinar la estructura de tallas y pesos medios, estimando longitudes de retención y rangos de selección. Se determinó la fracción bajo 30 y 36 cm de longitud total presentes en el copo y en el sobrecopo, ambos como indicadores del efecto selectivo que éstas producen. Los lances alternados permitieron verificar la disminución de los rendimientos de captura, tanto en número como en peso, aumentando los pesos medios de los ejemplares retenidos y disminuyendo la proporción de ejemplares bajo tallas de referencia, lo que indica la existencia de un efecto de escape en la fracción juvenil del stock.The evaluation of square mesh escape panels in bottom trawl nets used in the common hake fishery was carried out employing two complementary methodologies: top cover and alternated hauls. The top cover hauls were used to quantify the fraction of the catch that escapes through the panels and to determine the size structure and mean weight of the catch, estimating the retention sizes and selection ranges. The fractions under 30 and 36 cm of total length present in the codend and in the top cover were determined as proxies for the selective effect produced by the escape panels. The alternated hauls were used to verify the decrease in the catch rate, both in number and in weight, increasing the mean weight of the retained catch and decreasing the proportion under the reference length, for which we concluded that an escape effect does occur on the young fraction of the stock.

Benzo[a]pyrene and Benzo[k]fluoranthene in Some Processed Fish and Fish Products

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Olatunde S. Olatunji

2015-01-01

Full Text Available In this study, the concentration levels of the probable carcinogenic PAH fractions, benzo[a]pyrene (BaP and benzo[k]fluoranthrene (BkF in fillets of some processed fish species were investigated. Fish species comprising Merluccius poli (hake, Tyrsites atun (snoek, Seriola lalandi (yellow-tail and Brama brama (angel fish were bought in fish shops at Gordon’s Bay, Western Cape, South Africa. The fish were gutted, filleted and prepared for edibility by frying, grilling and boiling. Polycyclic aromatic hydrocarbons were extracted from each homogenized fish sample, cleaned-up using solid phase extraction (SPE, and analysed for the PAH fractions, BaP and BkF using a Gas Chromatograph coupled with a Flame Ionization Detector (GC-FID. The sum of the two PAHs (∑2PAH i.e., BaP and BkF ranged between 0.56 and 1.46 µg/kg, in all boiled, grilled and fried fish species. The fried fish extracts showed significantly higher (p < 0.05 abundance of ∑2PAH, than grilled and boiled fish. Dietary safety and PAHs toxicity was also discussed.

A review of Kudoa-induced myoliquefaction of marine fish species in South Africa and other countries

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Sun S. Henning

2013-11-01

Full Text Available Myoliquefaction of fish musculature results in customer quality complaints and in huge economic losses, especially with regard to Pacific hake (Merluccius productus, farm-reared Atlantic salmon (Salmo salar, South African pilchards (Sardinops ocellatus and Cape snoek (Thyrsites atun. Myoliquefaction, or jelly flesh, is caused by proteolytic enzymes released by the marine myxosporean parasite,Kudoa thyrsites, after the death of the fish. Currently there are no fast methods of detection for this microscopic parasite, and because myoliquefaction is evident only after 38-56 h post-mortem, infected fish inevitably reach the processor and/or consumer. Several methods of detection have been investigated, but most of these methods are time-consuming and/or result in destruction of the fish, and are thus impractical for fishing vessels and fish processors. Limited research is available on possible means of destroying or inhibiting the post-mortem activity of the parasitic proteolytic enzyme. Means such as manipulating post-mortem pH and temperature control have been suggested; leaving opportunities for research into food technology applications such as cold-chain management and ionising radiation.

Strategies to increase the hygienic and economic value of fresh fish: Biopreservation using lactic acid bacteria of marine origin.

Science.gov (United States)

Gómez-Sala, Beatriz; Herranz, Carmen; Díaz-Freitas, Belén; Hernández, Pablo E; Sala, Ana; Cintas, Luis M

2016-04-16

In this work we describe the development of a biopreservation strategy for fresh fish based on the use of bacteriocinogenic LAB of marine origin. For this purpose, two multibacteriocinogenic LAB strains, Lactobacillus curvatus BCS35 and Enterococcus faecium BNM58, previously isolated from fish and fish products were selected owing to their capability to inhibit the growth of several fish-spoilage and food-borne pathogenic bacteria. Two commercially important fish species were chosen, young hake (Merluccius merluccius) and megrim (Lepidorhombus boscii), and the specimens were acquired at the Marín (Pontevedra, Spain) retail fish market, after one night in the chilled hold of a near-shore fishing vessel. The biopreservation potential and the application strategies of these two LAB strains were first tested at a laboratory scale, where several batches of fresh fish were inoculated with: (i) the multibacteriocinogenic LAB culture(s) as protective culture(s); and/or (ii) their cell-free culture supernatant(s) as food ingredient(s), and (iii) the lyophilized bacteriocin preparation(s) as lyophilized food ingredient(s). All batches were stored in polystyrene boxes, permanently filled with ice at 0-2 °C, for 14 days. Microbiological analyses, as well as sensorial analyses, were carried out during the biopreservation trials. Subsequently, Lb. curvatus BCS35 was selected to up-scale the trials, and combinations of the three application methods were assayed. For this purpose, this strain was grown in a semi-industrial scale fermentor (150l) in modified MRS broth, and three batches of fresh fish were inoculated with the protective culture and/or food ingredient, and stored on ice in a chilled chamber at 0-2 °C at the Marín retail fish market for 14 days. Microbiological analyses were carried out during the storage period, showing that when Lb. curvatus BCS35 culture or the corresponding cell-free culture supernatant was used as protective culture or food ingredient

2007 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0710, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

2005 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0509, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

2009 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0903, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

2011 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (SH1103, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

PCR-SSCP of the 16S rRNA gene, a simple methodology for species identification of fish eggs and larvae

Directory of Open Access Journals (Sweden)

Eva Garcia-Vazquez

2006-10-01

Full Text Available Patterns of the 16S rRNA gene obtained in 8 and 12% acrylamide gels by the SSCP (Single Strand Conformation Polymorphism method were different for various marine fish species (Macrorhamphosus scolopax, Scomber scombrus, Lepidorhombus boscii, L. whiffiagonis, Trachurus trachurus, T. mediterraneus, Molva molva, Merluccius merluccius. SSCP patterns of this gene were employed to successfully identify formaldehyde-fixed eggs of different species (Merluccius merluccius, Scomber scombrus, Macrorhamphosus scolopax and L. whiffiagonis in plankton samples. The advantages of SSCPs in comparison with current genetic methods of egg identification are based on their technical simplicity and low price. The application of the PCR-SSCP methodology is proposed for routine genetic analyses in plankton surveys.

The 2011 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (SH1103, ME70)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

The 2005 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0509, EK500)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

The 2007 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0710, EK500)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

The 2003 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) (MF0316, EK500)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC) and the Pacific region...

Endoparasite fauna of five Gadiformes fish species from the coast of Chile: host ecology versus phylogeny.

Science.gov (United States)

Chávez, R A; González, M T; Oliva, M E; Valdivia, I M

2012-03-01

The aims of the present study were to compare, using multivariate analyses, the degree of similarity of the endoparasite fauna of five fish species belonging to the order Gadiformes: Merluccius gayi, Merluccius australis, Macruronus magellanicus (Gadoidei) and Micromesistius australis and Nezumia pulchella (Macrouroidei), from the southern and central Chilean coast, and to evaluate whether the composition of the endoparasite fauna was determined by phylogenetic or ecological relationships. We employed our database of Merluccius australis, M. magellanicus and Micromesistius australis, which was complemented with published information for M. magellanicus, Merluccius australis, Micromesistius australis, M. gayi and N. pulchella. A higher number of endoparasite species was recorded for Merluccius australis, Micromesistius australis and M. magellanicus, namely Anisakis sp. and Hepatoxylon trichiuri, which is the most prevalent parasite among these hosts. Aporocotyle wilhelmi and Hysterothylacium sp. were detected only in M. gayi, whereas Lepidapedon sp. was found exclusively in N. pulchella. These results suggest that fish ecology rather than host phylogeny was the most important factor for the determination of similarity in parasite composition. This result could be explained by the similar trophic patterns of hosts and by the predominance of generalist larval species among these fish parasite communities.

76 FR 66694 - New England Fishery Management Council (NEFMC); Public Meeting

Science.gov (United States)

2011-10-27

... meeting agenda. Following a lunch break, the Council will receive an update from the Northeast Regional... small mesh fishery which includes stocks of red hake, silver hake, and offshore hake. Thursday, November...

Geostatistical modelling of the spatial life history of post-larval deepwater hake Merluccius paradoxus in the Benguela Current Large Marine Ecosystem

DEFF Research Database (Denmark)

Jansen, T; Kristensen, K; Fairweather, T. P.

2017-01-01

paradoxus are not reflected in the current assessment and management practices for the Benguela Current Large Marine Ecosystem. In this study, we compiled data from multiple demersal trawl surveys from the entire distribution area and applied state-of the-art geostatistical population modelling (Geo...

Assessing the sources of the fishing down marine food web process in the Argentinean-Uruguayan Common Fishing Zone

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Andrés J. Jaureguizar

2008-03-01

Full Text Available The temporal trend in the mean trophic level (mTL, fisheries-in-balance index (FIB, trophic categories landing (TrC and landing profile (LP of the exploited marine community (82 species in the Argentinean-Uruguayan Common Fishing Zone (AUCFZ were examined from 1989 to 2003. The total landings (Yt (rs=-0.561; P< 0.05 and the Yt of carnivores and top predators has declined, while the Yt of herbivores, detritivores and omnivores has increased. Consequently, the mTL significantly decreased (rs =-0.88; P< 0.01 at a rate of 0.41 from 1991 (mTL =3.81 to 2003 (mTL =3.4, and the FIB index has declined in the last 6 years. The LP temporal pattern showed four periods with significant differences in their species composition and Primary Production Required, which shows a strong decline in the traditional fishery resources (i.e. Merluccius hubbsi, Micropogonias furnieri, and increases in crustacean (Chaceon notilis, molluscs (Zygochlamys patagonica and some fishes (Macrodon ancylodon, Macruronus magallanicus, Rajidae. The mTL trend reflects the changes in the AUCFZ landing structure. This was characterized by large, slow-growing and late-maturing species during the early 1990s, while during recent years, early 2000s, it was mainly characterized by medium-sized fishes, crustaceans and molluscs. The examination of the mTL, FBI, TrC trajectories and LP temporal pattern suggests that new fishery resources are developing or that the fishing effort has been redistributed from overexploited resources to lightly exploited resources. In addition, the examination of discriminator and common species, and the fact that traditional resources are being over-fished support the hypothesis that the mTL trend has been influenced more by the impacts of new fishing technologies than the changes in market-driven exploitation and environmental fluctuation. These results provide evidence of the fishing down process along AUCFZ.

Genetic diversity, endemism and phylogeny of lampreys within the genus Lampetra sensu stricto (Petromyzontiformes: Petromyzontidae) in western North America.

Science.gov (United States)

Boguski, D A; Reid, S B; Goodman, D H; Docker, M F

2012-11-01

Phylogenetic structure of four Lampetra species from the Pacific drainage of North America (western brook lamprey Lampetra richardsoni, Pacific brook lamprey Lampetra pacifica, river lamprey Lampetra ayresii and Kern brook lamprey Lampetra hubbsi) and unidentified Lampetra specimens (referred to as Lampetra sp.) from 36 locations was estimated using the mitochondrial cytochrome b gene. Maximum parsimony and Bayesian inferences did not correspond with any taxonomic scheme proposed to date. Rather, although L. richardsoni (from Alaska to California) and L. ayresii (from British Columbia to California) together constituted a well-supported clade distinct from several genetically divergent Lampetra populations in Oregon and California, these two species were not reciprocally monophyletic. The genetically divergent populations included L. pacifica (from the Columbia River basin) and L. hubbsi (from the Kern River basin) and four Lampetra sp. populations in Oregon (Siuslaw River and Fourmile Creek) and California (Kelsey and Mark West Creeks). These four Lampetra sp. populations showed genetic divergence between 2.3 and 5.7% from any known species (and up to 8.0% from each other), and may represent morphologically cryptic and thus previously undescribed species. A fifth population (from Paynes Creek, California) may represent a range extension of L. hubbsi into the Upper Sacramento River. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Potential risk assessment of metals in edible fish species for human consumption from the Eastern Aegean Sea.

Science.gov (United States)

Pazi, Idil; Gonul, L Tolga; Kucuksezgin, Filiz; Avaz, Gulsen; Tolun, Leyla; Unluoglu, Aydın; Karaaslan, Yakup; Gucver, S Mine; Koc Orhon, Aybala; Siltu, Esra; Olmez, Gulnur

2017-07-15

The levels of Hg, Cd, Pb, Cr, Cu and Zn were measured in the tissues of four edible fish species namely: Diplodus annularis, Pagellus erythrinus, Merluccius merluccius and Mullus barbatus, collected from the Turkish Coast of the Aegean Sea. Except for D. annularis, the levels of Cd and Pb in all fish tissues sampled in Aliaga Bay in 2009 were above the tolerable limits according to the Food and Agriculture Organization of the United Nations (FAO). Hg in P. erythrinus and M. barbatus were higher than the maximum permitted limits (FAO), while D. annularis and M. merluccius were lower than the limit for biota in the district of Aliaga. Although the Target Hazard Quotient (THQ) values for Cd, Pb, Cu, Cr, Zn in all fish samples were lower than 1.0, the THQ for Hg levels were higher than 1.0 for most of the samples. According to the THQ values, M. merluccius may be consumed in moderation from Aliaga Bay, while the consumption of M. barbatus and P. erythrinus collected from Aliaga Bay are potentially hazardous to human health due to the Hg concentrations. Fish collected from Izmir Bay can be consumed safely. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fish scales in sediments from off Callao, central Peru

Science.gov (United States)

Díaz-Ochoa, J. A.; Lange, C. B.; Pantoja, S.; De Lange, G. J.; Gutiérrez, D.; Muñoz, P.; Salamanca, M.

2009-07-01

We study fish scales as a proxy of fish abundance and preservation biases together with phosphorus from fish remains (P fish) in a sediment core retrieved off Callao, Peru (12°1'S, 77°42'W; water depth=179 m; core length=52 cm). We interpret our results as a function of changing redox conditions based on ratios of redox-sensitive trace elements (Cu/Al, Mo/Al, Ni/Al, Zn/Al, V/Al), terrigenous indicators (Fe in clays, Ti, Al), and biogenic proxies (CaCO 3, biogenic opal, total nitrogen, organic carbon, barite Ba). The core covers roughly 700 years of deposition, based on 210Pb activities extrapolated downcore and 14C dating at selected intervals. Our fish-scale record is dominated by anchovy ( Engraulis ringens) scales followed by hake ( Merluccius gayii) scales. The core presented an abrupt lithological change at 17 cm (corresponding to the early 19th century). Above that depth, it was laminated and was more organic-rich (10-15% organic carbon) than below, where the core was partly laminated and less organic-rich (Peru beginning in the early 19th century. Higher fish-scale contents and higher P fish/P total ratios were also observed within the upper 17 cm of the core. The behavior of biogenic proxies and redox-sensitive trace elements was similar; more reduced conditions corresponded to higher contents of CaCO 3, C org, total nitrogen and fish scales, suggesting that these proxies might convey an important preservation signal.

2012 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) and Pacific Sardine (Sardinops sagax) (SH1204, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC), the Fishery Resources...

Morphological and molecular characterisation of Aporocotyle margolisi Smith, 1967 (Digenea: Aporocotylidae) from the North Pacific hake Merluccius productus (Ayres) (Gadiformes: Merlucciidae) off Oregon, USA

Czech Academy of Sciences Publication Activity Database

Hernandez-Orts, J. S.; Hernández-Mena, D. I.; Alama-Bermejo, Gema; Kuchta, Roman; Jacobson, K. C.

2017-01-01

Roč. 94, č. 7 (2017), s. 819-829 ISSN 0165-5752 R&D Projects: GA ČR(CZ) GBP505/12/G112; GA ČR(CZ) GP14-28784P Institutional support: RVO:60077344 Keywords : blood flukes * phylogeny * platyhelminthes * sequences * sanguinicolidae * perciformes * models * gene Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine OBOR OECD: Veterinary science Impact factor: 1.181, year: 2016

Extending Vulnerability Assessment to Include Life Stages Considerations.

Science.gov (United States)

Hodgson, Emma E; Essington, Timothy E; Kaplan, Isaac C

2016-01-01

Species are experiencing a suite of novel stressors from anthropogenic activities that have impacts at multiple scales. Vulnerability assessment is one tool to evaluate the likely impacts that these stressors pose to species so that high-vulnerability cases can be identified and prioritized for monitoring, protection, or mitigation. Commonly used semi-quantitative methods lack a framework to explicitly account for differences in exposure to stressors and organism responses across life stages. Here we propose a modification to commonly used spatial vulnerability assessment methods that includes such an approach, using ocean acidification in the California Current as an illustrative case study. Life stage considerations were included by assessing vulnerability of each life stage to ocean acidification and were used to estimate population vulnerability in two ways. We set population vulnerability equal to: (1) the maximum stage vulnerability and (2) a weighted mean across all stages, with weights calculated using Lefkovitch matrix models. Vulnerability was found to vary across life stages for the six species explored in this case study: two krill-Euphausia pacifica and Thysanoessa spinifera, pteropod-Limacina helicina, pink shrimp-Pandalus jordani, Dungeness crab-Metacarcinus magister and Pacific hake-Merluccius productus. The maximum vulnerability estimates ranged from larval to subadult and adult stages with no consistent stage having maximum vulnerability across species. Similarly, integrated vulnerability metrics varied greatly across species. A comparison showed that some species had vulnerabilities that were similar between the two metrics, while other species' vulnerabilities varied substantially between the two metrics. These differences primarily resulted from cases where the most vulnerable stage had a low relative weight. We compare these methods and explore circumstances where each method may be appropriate.

Vacuum influence in the radurization of the Merluccius Merluccius Hubsi

International Nuclear Information System (INIS)

Ritacco, Miguel.

1976-02-01

A study was performed in order to determine the vacuum influence in the radurization of the merluce fillet in vaccum packed products irradiated at a dose of 0,5 Mrad. The product quality evaluation was performed using the periodical analysis of their organoleptic characteristics and determining the Trimetilamine values, Volatile Acid Number, Total Volatile Bases and Volatile Reducing Substances. The preservation state of the product was determined calculating the ''Edibility Index'' (Esub(I)). The results show that the vacuum packing conditions would allow to preserve at 4 deg C the merluce irradiated fillets during 48 days. (author) [es

Factors impacting on the microbiological quality and safety of ...

African Journals Online (AJOL)

Problems with the safety and shelf life of export hake have been raised by the Namibian fishing industry. This prompted an investigation into the factors that may have an impact on the microbiological quality and safety of processed hake. Samples were collected along the processing line; the general microbiological quality ...

The 2012 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) and Pacific Sardine (Sardinops sagax) (SH1204, ME70)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC), the Fishery Resources...

78 FR 26171 - Magnuson-Stevens Fishery Conservation and Management Act Provisions; Fisheries of the...

Science.gov (United States)

2013-05-03

... adopted an FY 2013 ABC for white hake based on the 2008 benchmark assessment for this stock, which was the... estimate current stock size and fishing mortality, and this model was approved at the last benchmark... hake benchmark stock assessment (SARC 56) was completed in February 2013. The results of the assessment...

The role of carrion supply in the abundance of deep-water fish off California.

Science.gov (United States)

Drazen, Jeffrey C; Bailey, David M; Ruhl, Henry A; Smith, Kenneth L

2012-01-01

Few time series of deep-sea systems exist from which the factors affecting abyssal fish populations can be evaluated. Previous analysis showed an increase in grenadier abundance, in the eastern North Pacific, which lagged epibenthic megafaunal abundance, mostly echinoderms, by 9-20 months. Subsequent diet studies suggested that carrion is the grenadier's most important food. Our goal was to evaluate if changes in carrion supply might drive the temporal changes in grenadier abundance. We analyzed a unique 17 year time series of abyssal grenadier abundance and size, collected at Station M (4100 m, 220 km offshore of Pt. Conception, California), and reaffirmed the increase in abundance and also showed an increase in mean size resulting in a ∼6 fold change in grenadier biomass. We compared this data with abundance estimates for surface living nekton (pacific hake and jack mackerel) eaten by the grenadiers as carrion. A significant positive correlation between Pacific hake (but not jack mackerel) and grenadiers was found. Hake seasonally migrate to the waters offshore of California to spawn. They are the most abundant nekton species in the region and the target of the largest commercial fishery off the west coast. The correlation to grenadier abundance was strongest when using hake abundance metrics from the area within 100 nmi of Station M. No significant correlation between grenadier abundance and hake biomass for the entire California current region was found. Given the results and grenadier longevity, migration is likely responsible for the results and the location of hake spawning probably is more important than the size of the spawning stock in understanding the dynamics of abyssal grenadier populations. Our results suggest that some abyssal fishes' population dynamics are controlled by the flux of large particles of carrion. Climate and fishing pressures affecting epipelagic fish stocks could readily modulate deep-sea fish dynamics.

Atomic-Oxygen Effects on POSS Polyimides in Low Earth Orbit

Science.gov (United States)

2012-01-11

Engineering, Long Beach, CA, May 12-16, 2002. (5) Koontz , S. L.; Leger, L. J.; Visentine, J. T.; Hunton, D. E.; Cross, J. B.; Hakes, C. L., “EOIM-III Mass...TP—1999-209260. (9) Koontz , S. L.; Leger, L. J.; Rickman, S. L.; Hakes, C. L.; Bui, D. T.; Hunton, D. E.; Cross, J. B. J. Spacecr. Rockets 1995, 32

Long-term variation in a central California pelagic forage assemblage

Science.gov (United States)

Ralston, Stephen; Field, John C.; Sakuma, Keith M.

2015-06-01

A continuous 23 year midwater trawl survey (1990-2012) of the epipelagic forage assemblage off the coast of central California (lat. 36°30‧-38°20‧ N) is described and analyzed. Twenty taxa occurred in ≥ 10% of the 2037 trawls that were completed at 40 distinct station locations. The dominant taxa sampled by the 9.5 mm mesh net included a suite of young-of-the-year (YOY) groundfish, including rockfish (Sebastes spp.) and Pacific hake (Merluccius productus), two clupeoids (Engraulis mordax and Sardinops sagax), krill (Euphausiacea), cephalopods (Doryteuthis opalescens and Octopus sp.), and a variety of mesopelagic species, i.e., Diaphus theta, Tarltonbeania crenularis, "other" lanternfish (Myctophidae), deep-sea smelts (Bathylagidae), and sergestid shrimp. Annual abundance estimates of the 20 taxa were obtained from analysis of variance models, which included year and station as main effects. Principal components analysis of the abundance estimates revealed that 61% of assemblage variance was explained by the first three components. The first component revealed a strong contrast in the abundance of: (a) YOY groundfish, market squid (D. opalescens), and krill with (b) mesopelagics and clupeoids; the second component was associated with long-term trends in abundance. An evaluation of 10 different published oceanographic data sets and CTD data collected during the survey indicated that seawater properties encountered each year were significantly correlated with abundance patterns, as were annual sea-level anomalies obtained from an analysis of AVISO satellite information. A comparison of our findings with several other recent studies of biological communities occurring in the California Current revealed a consistent structuring of forage assemblages, which we conjecture is primarily attributable to large-scale advection patterns in the California Current ecosystem.

PREVALENCE OF ANISAKID NEMATODE LARVAE INFECTING SOME MARINE FISHES FROM THE LIBYAN COAST.

Science.gov (United States)

Kassem, Hamed H; Bowashi, Salem Mohamed

2015-12-01

This study examined eight hundred ninety six marine fishes belonging to nine different fish species; Synodus saurus; Merluccius merluccius; Trachurus mediterraneus; Serranus cabrilla; Mullus surmuletus; Diplodus annularis; Spicara maena; Siganus rirulatus and Liza ramada. The fishes were bought from fish markets at five different sites on Libyan coast, from January to December 2013, for study the anisakids larvae among them. The results showed that 344/896 fishes (38.4%) were infected with Anisakids larvae. S. saurus was the highly infected (80.9%), followed by T mediterraneus (77.5%) but, S. cabrilla, S. maena, M merluccius, M surmuletus, and D. annularis were least anisakid infected showed rates of 58.2%, 53.8%, 43.7%, 36.7% & 3.6%, respectively. No parasites were in S. rirulatus and L, ramada. Ten species of Anisakids larvae was detected during the present study. Two Pseudoterranova sp. Larvae, two types of Anisakis larvae, Anisakis simplex larva and Anisakis sp. Larva, two types of Contracaecum sp. Larvae and four Hysterothylacium larvae. Females showed higher prevalence than males. The number of anisakid larvae varied according to body length and weight of infected fish, without significant difference between prevalence and seasons, but, a significant difference was between prevalence and regions.

Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

Science.gov (United States)

Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

2014-01-01

Crayfishes and other freshwater aquatic fauna are particularly at risk globally due to anthropogenic demand, manipulation and exploitation of freshwater resources and yet are often understudied. The Ozark faunal region of Missouri and Arkansas harbours a high level of aquatic biological diversity, especially in regard to endemic crayfishes. Three such endemics, Orconectes eupunctus,Orconectes marchandi and Cambarus hubbsi, are threatened by limited natural distribution and the invasions of Orconectes neglectus.

Introgression between ecologically distinct species following increased salinity in the Colorado Delta- Worldwide implications for impacted estuary diversity.

Science.gov (United States)

Lau, Clive L F; Jacobs, David K

2017-01-01

We investigate hybridization and introgression between ecologically distinct sister species of silverside fish in the Gulf of California through combined analysis of morphological, sequence, and genotypic data. Water diversions in the past century turned the Colorado River Delta from a normal estuary to a hypersaline inverse estuary, raising concerns for the local fauna, much of which is endangered. Salinity differences are known to generate ecological species pairs and we anticipated that loss of the fresher-water historic salinity regime could alter the adaptive factors maintaining distinction between the broadly distributed Gulf-endemic Colpichthys regis and the narrowly restricted Delta-endemic Colpichthys hubbsi , the species that experienced dramatic environmental change. In this altered environmental context, these long-isolated species (as revealed by Cytochrome b sequences) show genotypic (RAG1, microsatellites) evidence of active hybridization where the species ranges abut, as well as directional introgression from C. regis into the range center of C. hubbsi . Bayesian group assignment (STRUCTURE) on six microsatellite loci and multivariate analyses (DAPC) on both microsatellites and phenotypic data further support substantial recent admixture between the sister species. Although we find no evidence for recent population decline in C. hubbsi based on mitochondrial sequence, introgression may be placing an ancient ecological species at risk of extinction. Such introgressive extinction risk should also pertain to other ecological species historically sustained by the now changing Delta environment. More broadly, salinity gradient associated ecological speciation is evident in silverside species pairs in many estuarine systems around the world. Ecological species pairs among other taxa in such systems are likely poorly understood or cryptic. As water extraction accelerates in river systems worldwide, salinity gradients will necessarily be altered, impacting

Introgression between ecologically distinct species following increased salinity in the Colorado Delta- Worldwide implications for impacted estuary diversity

Directory of Open Access Journals (Sweden)

Clive L.F. Lau

2017-12-01

Full Text Available We investigate hybridization and introgression between ecologically distinct sister species of silverside fish in the Gulf of California through combined analysis of morphological, sequence, and genotypic data. Water diversions in the past century turned the Colorado River Delta from a normal estuary to a hypersaline inverse estuary, raising concerns for the local fauna, much of which is endangered. Salinity differences are known to generate ecological species pairs and we anticipated that loss of the fresher-water historic salinity regime could alter the adaptive factors maintaining distinction between the broadly distributed Gulf-endemic Colpichthys regis and the narrowly restricted Delta-endemic Colpichthys hubbsi, the species that experienced dramatic environmental change. In this altered environmental context, these long-isolated species (as revealed by Cytochrome b sequences show genotypic (RAG1, microsatellites evidence of active hybridization where the species ranges abut, as well as directional introgression from C. regis into the range center of C. hubbsi. Bayesian group assignment (STRUCTURE on six microsatellite loci and multivariate analyses (DAPC on both microsatellites and phenotypic data further support substantial recent admixture between the sister species. Although we find no evidence for recent population decline in C. hubbsi based on mitochondrial sequence, introgression may be placing an ancient ecological species at risk of extinction. Such introgressive extinction risk should also pertain to other ecological species historically sustained by the now changing Delta environment. More broadly, salinity gradient associated ecological speciation is evident in silverside species pairs in many estuarine systems around the world. Ecological species pairs among other taxa in such systems are likely poorly understood or cryptic. As water extraction accelerates in river systems worldwide, salinity gradients will necessarily be

Evaluation of three levels of selective devices relevant to management of the Danish Kattegat-Skagerrak Nephrops fishery

DEFF Research Database (Denmark)

Frandsen, Rikke; Holst, René; Madsen, Niels

2009-01-01

This study illuminates a range of technological options relevant to present legislation for regulating fish by-catch in a small-meshed Nephrops fishery. The selection of cod, haddock, hake, lemon sole, Nephrops, plaice, saithe, witch, and whiting were evaluated using the twin-trawl technique for...... parameters by species and confidence bands to compare the selective properties of different gear types. For cod, haddock, hake, Nephrops, plaice, and whiting we obtained estimates for all three gear variants, whereas we obtained estimates for lemon sole and witch only with the standard and the SMP codends...

Phenological and distributional shifts in ichthyoplankton associated with recent warming in the northeast Pacific Ocean.

Science.gov (United States)

Auth, Toby D; Daly, Elizabeth A; Brodeur, Richard D; Fisher, Jennifer L

2018-01-01

Understanding changes in the migratory and reproductive phenology of fish stocks in relation to climate change is critical for accurate ecosystem-based fisheries management. Relocation and changes in timing of reproduction can have dramatic effects upon the success of fish populations and throughout the food web. During anomalously warm conditions (1-4°C above normal) in the northeast Pacific Ocean during 2015-2016, we documented shifts in timing and spawning location of several pelagic fish stocks based on larval fish samples. Total larval concentrations in the northern California Current (NCC) during winter (January-March) 2015 and 2016 were the highest observed since annual collections first occurred in 1998, primarily due to increased abundances of Engraulis mordax (northern anchovy) and Sardinops sagax (Pacific sardine) larvae, which are normally summer spawning species in this region. Sardinops sagax and Merluccius productus (Pacific hake) exhibited an unprecedented early and northward spawning expansion during 2015-16. In addition, spawning duration was greatly increased for E. mordax, as the presence of larvae was observed throughout the majority of 2015-16, indicating prolonged and nearly continuous spawning of adults throughout the warm period. Larvae from all three of these species have never before been collected in the NCC as early in the year. In addition, other southern species were collected in the NCC during this period. This suggests that the spawning phenology and distribution of several ecologically and commercially important fish species dramatically and rapidly changed in response to the warming conditions occurring in 2014-2016, and could be an indication of future conditions under projected climate change. Changes in spawning timing and poleward migration of fish populations due to warmer ocean conditions or global climate change will negatively impact areas that were historically dependent on these fish, and change the food web structure

Tradition haking s up

Indian Academy of Sciences (India)

more years before her hopes become a real- ... spend time with my children whenever possible. Although I ... 12 years of her marriage traveling between. India and ... The real breakthrough for Asia, according to Vijayalakshmi, will come only ...

Concentrations of polybrominated diphenyl ethers, hexachlorobenzene and polycyclic aromatic hydrocarbons in various foodstuffs before and after cooking.

Science.gov (United States)

Perelló, Gemma; Martí-Cid, Roser; Castell, Victoria; Llobet, Juan M; Domingo, José L

2009-04-01

The cooking-induced changes in the levels of polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), and 16 polycyclic aromatic hydrocarbons (PAHs) in various foodstuffs were investigated. Foods included fish (sardine, hake and tuna), meat (veal steak, loin of pork, breast and thigh of chicken, and steak and rib of lamb), string bean, potato, rice, and olive oil. For each food item, raw and cooked (fried, grilled, roasted, boiled) samples were analyzed. There were some variations in the concentrations of PBDEs before and after cooking. However, they depended not only on the cooking process, but mainly on the specific food item. The highest HCB concentrations were found in sardine, being lower in cooked samples. All cooking processes enhanced HCB levels in hake, while very scarce differences could be noted in tuna (raw and cooked). In general terms, the highest PAH concentrations were found after frying by being the values especially notable in fish, excepting hake, where the highest total PAH levels corresponded to roasted samples. The results of this study show that, in general, cooking processes are only of a limited value as a means of reducing PBDE, HCB and PAH concentrations in food.

A model of trophic flows in the northern Benguela upwelling system during the 1980s

DEFF Research Database (Denmark)

Shannon, L.J.; Jarre, Astrid

1999-01-01

A model of trophic flows through the northern Benguela between 1980 and 1989 was constructed using the ECOPATH approach. The model serves to close the temporal gap between models of the system for the 1970s and 1990s. The aim is to provide a workable model, with the intention of encouraging...... in the northern Benguela during the 1980s was high, comparable to that of the Peruvian system in the 1960s and almost double that of the northern Benguela during the 1970s. Horse mackerel and hake catches were both high, with fishing on hake being ecologically more expensive. Biomass of benthic producers, meio...

Distribución del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur Ichthyoplankton distribution in South Patagonia, Chile: potential effects of ice melting from the Southern Ice Field

Directory of Open Access Journals (Sweden)

Mauricio F Landaeta

2011-07-01

Full Text Available Durante octubre-noviembre de 2009 se realizó un crucero oceanográfico entre 50 y 53°S de Chile austral, en las cercanías del glaciar Campos de Hielo Sur. Las estaciones cercanas al glaciar presentaron baja temperatura (1-3°C y salinidad ( 0,1 ciclos s-1. Los principales taxa del ictioplancton fueron huevos y larvas de sardina fueguina Sprattus fuegensis, pez hacha Maurolicus parvipinnis, Macrouridae y merluza austral Merluccius australis. El desove principal de S. fuegensis (~ 8000 huevos 10 m-2 ocurrió en zonas mezcladas de la plataforma continental adyacente, mientras que el desove de M. parvipinnis ocurrió en canales intermedios asociado a valores intermedios de estabilidad (N~0,06 ciclos s-1. Se observó una nula o baja abundancia de huevos y larvas de peces en las cercanías del glaciar, y la abundancia de huevos de M. parvipinnis estuvo relacionada positivamente con la temperatura y salinidad de la columna de agua y negativamente con la estabilidad de la columna de agua. Además, hubo una relación negativa entre la densidad del agua de mar y el diámetro de los huevos de S. fuegensis. La relación entre deshielo e ictioplancton podría tener consecuencias en el transporte advectivo y mortalidad masiva de huevos y larvas de peces y el acople pelágico-bentónico en la Patagonia austral de Chile. Como el cambio climático global ha incrementado los deshielos de glaciares en latitudes altas, y el aumento del ingreso de aguas de baja temperatura y salinidad podría tener consecuencias en el ictioplancton de la Patagonia chilena.In October-November 2009, an oceanographic survey was carried out between 50 and 53°S off southern Chile, near the Southern Ice Field. The stations near the glacier showed low temperatures (1-3°C and salinity ( 0.1 cycles s-1. Main ichthyoplankton taxa were eggs and larvae of southern sprat Sprattus fuegensis, lightfish Maurolicus parvipinnis, Macrouridae, and southern hake Merluccius australis. The main

Deep-water fisheries at the Atlantic Frontier

Science.gov (United States)

Gordon, J. D. M.

2001-05-01

( Micromesistius poutassou). The other semipelagic fishery is on spawning aggregations of the greater silver smelt or argentine ( Argentina silus). Spanish and UK vessels that target mainly hake ( Merluccius merluccius) and a Norwegian fleet that targets ling ( Molva molva), blue ling and tusk ( Brosme brosme) dominate the upper slope longline fishery. West of Shetland, the fishery on the upper slope has some similarities with that of the Hebridean slope, with anglerfish and blue ling being important target species. A quite different fishery occurs in the transition zone between the Atlantic and Norwegian Sea waters. Here the main target species is Greenland halibut ( Reinhardtius hippoglossoides). Below the transition zone biomass decreases rapidly and there is no fishery. It is generally agreed that many deep-water species have slow growth, a high age at first maturity and a low fecundity, which makes them vulnerable to over-exploitation. Other features of these fishes such as high mortality of discards and escapees will add to the problems. Despite this the only management procedures in place are general limitation of effort measures within the area of jurisdiction of the European Union.

Estrategias de la anchoíta en un mar de tiburones: Las pymes conserveras marplatenses durante la valoración financiera [1975-2006

OpenAIRE

José Mateo; Gonzalo Yurkievich

2010-01-01

Desde los años 70 Argentina se consolidó como un país pesquero, siendo la merluza hubbsi la principal especie capturada y exportada. Desde fines de la década de 1990 pequeñas y medianas empresas supieron conciliar extracción, manufactura y mercados explotando especies costeras, entre las cuales se destaca la anchoíta. El presente trabajo se centra en las estrategias de gestión, organización e innovación de Coomarpes e Indupesa, empresas que han subsistido en un mercado dominado por un poderos...

Development of the chondrocranium of the shallow-water Cape ...

African Journals Online (AJOL)

1988-01-15

Jan 15, 1988 ... Both the auditory capsules and the occipital arches take part in the development of the tectum synoticum. The tectum posterius does not develop separately, but as a posterior extension of the tectum synoticum. Die ontwikkeling die neurokranium van Merluccius capensis word beskryf vanaf die vroegste ...

77 FR 51521 - New England Fishery Management Council; Public Meeting

Science.gov (United States)

2012-08-24

..., Georges Bank yellowtail flounder, witch flounder, plaice, and Georges Bank/Gulf of Maine white hake... meeting is physically accessible to people with disabilities. Requests for sign language interpretation or...

NEFSC Small Pelagics Acoustic/Midwater Trawl Survey (DE9903, EK500)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The small pelagics cruise will map the distribution of small pelagic species such as Atlantic mackerel, Atlantic herring, silver hake, butterfish, and squid, in the...

Copper-Based Torpedo Guidance Wire: Applications and Environmental Considerations

Science.gov (United States)

2013-06-01

whose swimming or feeding behaviors place them near the ocean floor. Additionally, an emphasis was placed on those animals with benthic feeding habits ...may suck in their prey and swallow them whole (Pitman, 2002; Heyning and Mead, 1996). However their feeding habits do not include digging through... feed on a various epipelagic and mesopelagic cephalopods, teleosts, Merluccius productus, crustaceans , elasmobranchs, cyclostomes, and tunicates

Spatial overlap of shark nursery areas and the salmon farming industry influences the trophic ecology of Squalus acanthias on the southern coast of Chile.

Science.gov (United States)

Gaitán-Espitia, Juan Diego; Gómez, Daniela; Hobday, Alistair J; Daley, Ross; Lamilla, Julio; Cárdenas, Leyla

2017-06-01

Potential interactions between marine predators and humans arise in the southern coast of Chile where predator feeding and reproduction sites overlap with fisheries and aquaculture. Here, we assess the potential effects of intensive salmon aquaculture on food habits, growth, and reproduction of a common predator, the spiny dogfish-identified as Squalus acanthias via genetic barcoding. A total of 102 (89 females and 13 males) individuals were collected during winter and summer of 2013-2014 from the Chiloé Sea where salmon aquaculture activities are concentrated. The low frequency of males in our study suggests spatial segregation of sex, while immature and mature females spatially overlapped in both seasons. Female spiny dogfish showed a functional specialist behavior as indicated by the small number of prey items and the relative high importance of the austral hake and salmon pellets in the diet. Immature sharks fed more on pellets and anchovies than the larger hake-preferring mature females. Our results also indicate that spiny dogfish switch prey (anchovy to hake) to take advantage of seasonal changes in prey availability. Despite differences in the trophic patterns of S. acanthias due to the spatial association with intensive salmon farming, in this region, there appears to be no difference in fecundity or size at maturity compared to other populations. Although no demographic effects were detected, we suggest that a range of additional factors should be considered before concluding that intensive aquaculture does not have any impact on these marine predators.

New gadiform fishes (Teleostei, Gadiformes) from the Miocene of Algeria

Science.gov (United States)

Carnevale, Giorgio

2007-02-01

As part of the completion of studies on the Miocene fishes of the Chelif Basin (north-western Algeria), this paper represents a contribution to the knowledge of the Messinian gadiform diversity of this western Mediterranean, semi-enclosed, Neogene basin. A new genus and species of the family Macrouridae is erected ( Razelainia paradoxa n. gen. et sp.), two specimens are tentatively referred to already existing taxa ( Gadiculus cf. jonas; Merluccius cf. merluccius), and a species formerly assigned to the gadid genus Brosme is transferred to the genus Gaidropsarus ( Gaidropsarus murdjadjensis). The macrourid Razelainia paradoxa n. gen. et sp. is characterized by an unusual combination of: plesiomorphic gadiform features, such as low vertebral number (presumed), well-developed caudal-fin rays, presence of a single continuous dorsal fin originating just posterior to the neurocranium, anal-fin rays slightly longer than dorsal-fin rays; and derived, typically macrourid features, such as the presence of spinoid scales and the anterior anal-fin pterygiophores extending forward over the abdominal wall. A paleoecological analysis reveals that the Messinian gadiform assemblage of the Chelif Basin had a subtropical/warm temperate affinity, with a marked north-eastern Atlantic-Mediterranean biogeographic character.

Browse Title Index

African Journals Online (AJOL)

Items 401 - 450 of 1060 ... ... South African Cape hakes using generalised additive models, Abstract ... between three commercial fish associated with artificial reefs in a tropical ... Vol 27, No 3 (2005), Food habits of some deep-sea fish off South ...

Factors impacting on the microbiological quality and safety of ...

African Journals Online (AJOL)

hope&shola

2010-12-06

Dec 6, 2010 ... microbiological quality and safety of processed hake. Samples were collected along the processing line; the general microbiological quality (mesophylic and psychrotrophic aerobic plate counts), total. Vibrio species and common fish spoilage bacterial counts were performed. The results constantly showed ...

Regime Shifts and Resilience in Fisheries Management

NARCIS (Netherlands)

Li, Chuan Zhong; Villasante, Sebastian; Zhu, Xueqin

2016-01-01

We investigate the role of potential regime shifts in Argentinean hake fishery and the inter-linkage between ecological and economic resilience. We develop a theoretical model incorporated with the hazard function for resource management under alternative conditions, and derive the corrective

The biology and distribution of the monkfish Lophius vomerinus off ...

African Journals Online (AJOL)

The monkfish Lophius vomerinus is economically the most important bycatch species in the South African demersal hake fishery. To assist in the development of a bycatch management plan for the species, age and growth characteristics, reproductive and feeding biology, and distribution patterns were investigated.

77 FR 47373 - New England Fishery Management Council; Public Meeting

Science.gov (United States)

2012-08-08

..., Southern New England/Mid-Atlantic yellowtail flounder, Georges Bank yellowtail flounder, witch flounder, plaice and Georges Bank/Gulf of Maine white hake. The committee may not develop all the recommendations... accessible to people with disabilities. Requests for sign language interpretation or other auxiliary aids...

76 FR 57944 - Fisheries of the Northeastern United States; Northeast Multispecies Fisheries, Small-Mesh...

Science.gov (United States)

2011-09-19

... FURTHER INFORMATION CONTACT: Moira Kelly, Fishery Policy Analyst, (978) 281-9218, [email protected] catch (ABC) limits based on recommendations from its Scientific and Statistical Committee (SSC), at its September 2011 meeting. The SSC has recommended separate ABCs by stock or stock group: Northern red hake...

78 FR 64889 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Emergency Rule...

Science.gov (United States)

2013-10-30

... Catch (ABC) and Annual Catch Limit (ACL) for GB yellowtail flounder and white hake, and the 1.85-percent....noaa.gov/sfd/sfdmulti.html . FOR FURTHER INFORMATION CONTACT: Melissa Hooper, Fishery Policy Analyst... these emergency measures. 1. FY 2013 GB Yellowtail Flounder ABC The emergency specifications extended...

Low Oxygen Water (LOW) variability in the Benguela system: key processes and forcing scales relevant to forecasting

CSIR Research Space (South Africa)

Monteiro, PMS

2006-09-01

Full Text Available or mortality of rock lobster in the southern Benguela; Medium term (2 month) forecasting of the intensification of the remote forcing of ETSA derived LOW which has a bearing on the Namibian hake fishery These two scales are discussed in detail in the companion...

Movements of immature European Honey Buzzards Pernis apivorus in tropical Africa

NARCIS (Netherlands)

Strandberg, Roine; Hake, Mikael; Klaassen, Raymond H. G.; Alerstam, Thomas

2012-01-01

Strandberg R., Hake M., Klaassen R.H.G. & Alerstam T. 2012. Movements of immature European Honey Buzzards Pernis apivorus in tropical Africa. Ardea 100: 157-162. Immature European Honey Buzzards Pernis apivorus are believed to remain in tropical Africa during the first years of their lives. We

Risk assessment of methylmercury in five European countries considering the national seafood consumption patterns

DEFF Research Database (Denmark)

Jacobs, Silke; Sioen, Isabelle; Jacxsens, Liesbeth

2017-01-01

confirms the substantial contribution of tuna to MeHg exposure in each of the countries. Also hake, cod, sea bream, sea bass and octopus are identified as important contributors. From this study, it is concluded that a country-specific seafood consumption advice is needed. Policy makers may adopt...

78 FR 18187 - Magnuson-Stevens Fishery Conservation and Management Act Provisions; Fisheries of the...

Science.gov (United States)

2013-03-25

... overfishing and was overfished. A new benchmark assessment (SARC 54) was completed for this stock in June 2012... stock was overfished. Final results from the February 2013 benchmark assessment for white hake are... Management Council (Council) as part of the biennial review process to respond to updated stock information...

78 FR 19367 - Magnuson-Stevens Fishery Conservation and Management Act Provisions; Fisheries of the...

Science.gov (United States)

2013-03-29

... assessment for white hake was completed in 2008. A benchmark assessment for this stock was completed in... years (FYs) 2013-2015, including 2013 total allowable catches (TACs) for the three U.S./Canada stocks... management measures for this stock consistent with the proposed rebuilding strategy. This action also...

The spawning products of fish living in upwelling ecosystems have ...

African Journals Online (AJOL)

denise

Normally, hake spawn offshore near the bottom at depths of. 150–400 m. ... eyes or mouth, and display little swimming activity during their first hours, but laboratory observations have revealed subsequent ... Based on current field observations, on buoyancy measure- ...... wind-induced turbulence will not influence their ver-.

78 FR 21115 - Magnuson-Stevens Act Provisions; General Provisions for Domestic Fisheries; Application for...

Science.gov (United States)

2013-04-09

... monkfish for sale, but the sampling locations are determined by CCE. To conduct compensation fishing in... as to how the waiver could influence fishing behavior, and if it could increase the likelihood of an... white hake and witch flounder, which would be landed for commercial sale. All catch of Northeast...

Seabird bycatch in the demersal longline fishery off southern Africa ...

African Journals Online (AJOL)

Differences in catch rates between trips were investigated and moon phase, area and gear type were all found to be significant. All birds were caught using light gear, which sank significantly slower than heavier gear. The South African hake longline fishery has a relatively small impact on pelagic seabird populations ...

Determining optimal pinger spacing for harbour porpoise bycatch mitigation

DEFF Research Database (Denmark)

Larsen, Finn; Krog, Carsten; Eigaard, Ole Ritzau

2013-01-01

A trial was conducted in the Danish North Sea hake gillnet fishery in July to September 2006 to determine whether the spacing of the Aquatec AQUAmark100 pinger could be increased without reducing the effectiveness of the pinger in mitigating harbour porpoise bycatch. The trial was designed as a c...

Estrategias de la anchoíta en un mar de tiburones: Las pymes conserveras marplatenses durante la valoración financiera [1975-2006

Directory of Open Access Journals (Sweden)

José Mateo

2010-04-01

Full Text Available Desde los años 70' Argentina se consolidó como un país pesquero, siendo la merluza hubbsi la principal especie capturada y exportada. Desde fines de la década de 1990 pequeñas y medianas empresas supieron conciliar extracción, manufactura y mercados explotando especies costeras, entre las cuales se destaca la anchoíta. El presente trabajo se centra en las estrategias de gestión, organización e innovación de Coomarpes e Indupesa, empresas que han subsistido en un mercado dominado por un poderoso oligopolio interno y por capitales foráneos que depredan el mar argentino y exportan productos con escaso agregado de valor hacia mercados europeos y asiáticos

Near-shore distribution of Heaviside's ( Cephalorhynchus heavisidii ...

African Journals Online (AJOL)

Heaviside's dolphins were found in shallower, cooler water than dusky dolphins and were more likely to be seen during brighter phases of the moon (when nocturnal light conditions may influence the vertical migration patterns of prey) and in areas of high hake abundance. Near-shore fishing activity was higher in the ...

Specific IgE to fish extracts does not predict allergy to specific species within an adult fish allergic population.

Science.gov (United States)

Schulkes, Karlijn Jg; Klemans, Rob Jb; Knigge, Lidy; de Bruin-Weller, Marjolein; Bruijnzeel-Koomen, Carla Afm; Marknell deWitt, Asa; Lidholm, Jonas; Knulst, André C

2014-01-01

Fish is an important cause of food allergy. Studies on fish allergy are scarce and in most cases limited to serological evaluation. Our objective was to study patterns of self-reported allergy and tolerance to different commonly consumed fish species and its correlation to IgE sensitization to the same species. Thirty-eight adult fish allergic patients completed a questionnaire regarding atopy, age of onset and symptoms to 13 commonly consumed fish species in the Netherlands (pangasius, cod, herring, eel, hake, pollock, mackerel, tilapia, salmon, sardine, tuna, plaice and swordfish). Specific IgE to these fish extracts were analyzed by ImmunoCAP. Median age of onset of fish allergy was 8.5 years. Severe reactions were reported by the majority of patients (n = 20 (53%) respiratory and of these 20 patients, 6 also had cardiovascular symptoms). After diagnosis, 66% of the patients had eliminated all fish from their diet. Allergy to all species ever tried was reported by 59%. In relation to species ever tried, cod (84%) and herring (79%) were the most frequently reported culprit species while hake (57%) and swordfish (55%) were the least frequent. A positive sIgE (value ≥ 0.35 kUA/L) to the culprit species ranged between 50% (swordfish) and 100% (hake). In tolerant patients, a negative sIgE (value allergy or tolerance was 82% and 25%, respectively. Sensitization to cod parvalbumin (Gad c 1) was present in 77% of all patients. Serological cross-reactivity between fish species is frequent, but in a significant proportion of patients, clinical relevance appears to be limited to only certain species. A well-taken history or food challenge is required for discrimination between allergy to the different fish species.

Evaluation of the trace elements and the total mercury concentration in fishes commercialized at the Cubatao city, Sao Paulo, Brazil

International Nuclear Information System (INIS)

Fonseca, Barbara C.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Debora I.T.; Braga, Elisabete S.

2009-01-01

This paper evaluates the total Hg and the trace elements As, Br, Co, Cr and Rb concentrations in muscle of commercially important fishes at the Cubatao, Sao Paulo, Brazil, region. The following carnivore species were analysed: jew fish (Micropogonias furnieri), girl leg (Menticirrhus americanus), hake (Macrodon ancylodon), and plant eaters, sardine (Sardella braziliensis) and grey mullet (Mugil liza), representing a total of 58 samples. The analysed trace elements were determined through the neutron analysis activation (NAA) and total Hg, through the atomic absorption spectrometry with cold vapor generation (CV AAS). The analysed elements present a great concentration variation, not only among individuals of the same specie, but also among all the analysed species. The total Hg concentration were highly significant, with the predator species jew fish, girl leg and hake presenting concentrations larger than the non predator species sardine and grey mullet. Nevertheless, the content of total Hg remained bellow the limits established by the Brazilian legislation which is the 500 μg kg -1 for the non predator species, and the 1000 μg -1 for the predator species (humid weight)

Effects of natural and synthetic soil conditioners on soil moisture ...

African Journals Online (AJOL)

The efficacy of a natural soil conditioner, Coco-Peat (C-P), and synthetic soil conditioners, Terawet (T-200) and Teraflow (T-F), in improving soil moisture content were examined on five Ghanaian soil series (Akroso, Akuse, Amo, Hake and Oyarifa). In general, the water retention of T-200 and C-P treated soils were similar ...

75 FR 59154 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Trip Limit...

Science.gov (United States)

2010-09-27

... (453.6 kg) per trip, Georges Bank (GB) yellowtail flounder to 100 lb (45.4 kg) per trip, and white hake... the U.S./Canada Management Area to include the entire Western U.S./Canada Area; and authorizes the use of the rope separator trawl in the Western U.S./Canada Area for NE multispecies vessels fishing in...

Anthropogenic impact in the Santa Maria di Leuca cold-water coral province (Mediterranean Sea): Observations and conservation straits

Science.gov (United States)

D'Onghia, G.; Calculli, C.; Capezzuto, F.; Carlucci, R.; Carluccio, A.; Grehan, A.; Indennidate, A.; Maiorano, P.; Mastrototaro, F.; Pollice, A.; Russo, T.; Savini, A.; Sion, L.; Tursi, A.

2017-11-01

, Merluccius merluccius and Conger conger while those from trawling mostly consisted of Aristeus antennatus, Aristaeomorpha foliacea and M. merluccius. The information collected during the observers' program and VMS data indicated greater impact due to trawling than longlining. The conservation and effective management of this vulnerable marine ecosystem remain difficult.

Military Chapels and Chaplains: A Bibliography of Books and Periodical Articles.

Science.gov (United States)

1982-07-29

Dave . "Fifteen len of God," AD, 22:47, 48,.Sep 1967. Hake, Janet. "Helping Rands," SOL, 30:44-46, May 1975. _ "Sunday Every Day," SOL, 31:28-31, Oct...Chaplain," LCIM, 27:10-12, Oct 1943. Yates, Julian -. "The Chaplain," ;A:J, 70:550, 1932-33. Zielinski , Constantine Z. "The Chaplain and Stimulation

Trawl catch composition during different fishing intensity periods in two Mediterranean demersal fishing grounds

Directory of Open Access Journals (Sweden)

Pilar Sánchez

2007-12-01

Full Text Available The study was carried out in two fishing grounds on the Mediterranean continental shelf: one in the Adriatic Sea and one in the Catalan Sea. Samplings on board otter trawlers were performed from November 2002 to December 2003 in the Catalan Sea and from February 2003 to January 2004 in the Adriatic Sea. The Adriatic fishing ground was affected by high fishing intensity from January to June, while the Catalan area was highly exploited from September to February. Fishing activity in the Adriatic area was closed for 45 days, and 62 days in the Catalan area; both periods were in summer. Totals of 92 and 88 species were collected in the Adriatic and Catalan fishing grounds respectively. The species composition of the retained and discarded fractions showed close agreement between the two areas. Mullus barbatus showed very low discard rates in both areas, as well as Loligo vulgaris in the Catalan Sea and Merluccius merluccius in the Adriatic Sea. In both fishing grounds Squilla mantis showed high catch rates with low discards, except in March in the Catalan area. In the Adriatic Sea Liocarcinus depurator was characterized by large discard fractions. In both fishing grounds the retained fraction was slightly higher in the high fishing intensity periods than in the low intensity ones (Adriatic Sea: 0.613 vs 0.524; Catalan Sea: 0.597 vs 0.539, even though the Kruskall Wallis test revealed significant differences (p

Mercury content in Chilean fish and estimated intake levels.

Science.gov (United States)

Cortes, Sandra; Fortt, Antonia

2007-09-01

The intake of fish products is a major public health concern due to possible methyl mercury exposure, which is especially toxic to the human nervous system. This pilot study (n = 46) was designed to determine mercury concentrations in fish products for national consumption (Chilean jack mackerel, hake, Chilean mussel, tuna) and for export (salmon, Patagonian toothfish, swordfish, southern hake), and to estimate the exposure of the general population. The fish products were collected from markets in Talcahuano, Puerto Montt and Santiago. Samples were analyzed at the National Environmental Center by cold vapor atomic absorption spectrophotometry. Mercury levels in swordfish and one canned tuna sample exceeded levels prescribed by national and international standards. The remaining two export products (Patagonian toothfish, also known as Chilean sea bass, and salmon) complied with international limits, which are more demanding than Chilean regulations. Theoretical estimates of mercury intake varied from 0.08 to 3.8 microg kg(-1) bw day(-1) for high fish consumers, exceeding the provisional tolerable intake for tuna, Chilean seabass, Chilean jack mackerel and swordfish. This group appears to be at the greatest risk from mercury contamination among the Chilean population.

Evaluation of the trace elements and the total mercury concentration in fishes commercialized at the Cubatao city, Sao Paulo, Brazil; Avaliavao da concentracao de elementos traco e de mercurio total em pescados comercializados na cidade de Cubatao, Estado de Sao Paulo

Energy Technology Data Exchange (ETDEWEB)

Fonseca, Barbara C.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Debora I.T., E-mail: ba_cortopassi@hotmail.co [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Braga, Elisabete S., E-mail: edsbraga@usp.b [Universidade de Sao Paulo (LABNUT/USP), SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Macronutrientes e Tracos no Oceano

2009-07-01

This paper evaluates the total Hg and the trace elements As, Br, Co, Cr and Rb concentrations in muscle of commercially important fishes at the Cubatao, Sao Paulo, Brazil, region. The following carnivore species were analysed: jew fish (Micropogonias furnieri), girl leg (Menticirrhus americanus), hake (Macrodon ancylodon), and plant eaters, sardine (Sardella braziliensis) and grey mullet (Mugil liza), representing a total of 58 samples. The analysed trace elements were determined through the neutron analysis activation (NAA) and total Hg, through the atomic absorption spectrometry with cold vapor generation (CV AAS). The analysed elements present a great concentration variation, not only among individuals of the same specie, but also among all the analysed species. The total Hg concentration were highly significant, with the predator species jew fish, girl leg and hake presenting concentrations larger than the non predator species sardine and grey mullet. Nevertheless, the content of total Hg remained bellow the limits established by the Brazilian legislation which is the 500 {mu}g kg{sup -1} for the non predator species, and the 1000 {mu}g{sup -1} for the predator species (humid weight)

White fish reduces cardiovascular risk factors in patients with metabolic syndrome: the WISH-CARE study, a multicenter randomized clinical trial.

Science.gov (United States)

Vázquez, C; Botella-Carretero, J I; Corella, D; Fiol, M; Lage, M; Lurbe, E; Richart, C; Fernández-Real, J M; Fuentes, F; Ordóñez, A; de Cos, A I; Salas-Salvadó, J; Burguera, B; Estruch, R; Ros, E; Pastor, O; Casanueva, F F

2014-03-01

Reduction of cardiovascular risk with high consumption of fish in diet is still a matter of debate, and concerns about heavy metal contamination have limited consumption of oily fish. We aimed to evaluate the effect of regular ingestion of white fish on cardiovascular risk factors in patients with metabolic syndrome. Multicenter randomized crossover clinical trial including 273 individuals with metabolic syndrome. An 8-week only-one dietary intervention: 100 g/d of white fish (Namibia hake) with advice on a healthy diet, compared with no fish or seafood with advice on a healthy diet. Outcomes were lipid profile, individual components of the metabolic syndrome, serum insulin concentrations, homeostasis model of insulin resistance, serum C-reactive protein and serum fatty acid levels. We found a significant lowering effect of the intervention with white fish on waist circumference (P rise (P syndrome, regular consumption of hake reduces LDL cholesterol concentrations, waist circumference and blood pressure components of the metabolic syndrome. White Fish for Cardiovascular Risk Factors in Patients with Metabolic Syndrome Study, Registered under ClinicalTrials.gov Identifier: NCT01758601. Copyright © 2013 Elsevier B.V. All rights reserved.

Paleoecological studies on variability in marine fish populations: A long-term perspective on the impacts of climatic change on marine ecosystems

Science.gov (United States)

Finney, Bruce P.; Alheit, Jürgen; Emeis, Kay-Christian; Field, David B.; Gutiérrez, Dimitri; Struck, Ulrich

2010-02-01

The use of historical fishing records to understand relationships between climatic change and fish abundance is limited by the relatively short duration of these records, and complications due to the strong influence of human activity in addition to climatic change. Sedimentary records containing scales, bones or geochemical proxies of variability in fish populations provide unique insights on long-term ecosystem dynamics and relationships with climatic change. Available records from Holocene sediments are summarized and synthesized. The records are from several widespread locations near or along the continental margins of the South Atlantic and Pacific oceans, including Alaska, USA (Pacific salmon), Saanich and Effingham Inlets, British Columbia, Canada (pelagic fish), Santa Barbara Basin, California, USA (Northern anchovies and Pacific sardines), Gulf of California, Mexico (Pacific sardines, Northern anchovies and Pacific hake), Peru upwelling system (sardines, anchovies and hake), and Benguela Current System, South Africa (sardines, anchovies and hake). These records demonstrate that fish population sizes are not constant, and varied significantly over a range of time scales prior to the advent of large-scale commercial fishing. In addition to the decadal-scale variability commonly observed in historical records, the long-term records reveal substantial variability over centennial and millennial time scales. Shifts in abundance are often, but not always, correlated with regional and/or global climatic changes. The long-term perspective reveals different patterns of variability in fish populations, as well as fish-climate relationships, than suggested by analysis of historical records. Many records suggest prominent changes in fish abundance at ca. 1000-1200 AD, during the Little Ice Age, and during the transition at the end of the Little Ice Age in the 19th century that may be correlative, and that were likely driven by major hemispheric or global

THE INFLUENCE OF SLOW THAWING ON EVOLUTION OF SOME BIOCHEMICAL COMPOUNDS IN FROZEN FISHES

Directory of Open Access Journals (Sweden)

Marcel AVRAMIUC

2017-06-01

Full Text Available The aim of this work was to study the evolution of pH, amino nitrogen and nitrogen from aminoacids in four fish species, during 48 hours of slow thawing, in order to assess the fish spoilage speed in these keeping conditions. The biological material was represented by frozen fishes (carp, catfish, mackerel and hake which were subjected to slow thawing at room temperature (+20..+22°C, by analysing, at certain time intervals, pH, amino nitrogen - AN (mg %, and nitrogen from aminoacids - NAA (g %. The pH was determined with a digital pH-meter type Hanna, and the nitrogen from aminoacids according to Sörensen method. The amino nitrogen was determined by the difference between the nitrogen content of volatile bases and the nitrogen content of the ammonia and primary amines. As compared to frozen samples, both pH and the amino nitrogen values of all fish samples showed constant and significant increases up to the end of the analyzed period, while the nitrogen from aminoacids only in the first 30 hours of thawing. The amino nitrogen and the nitrogen from amino acids values have indicated the highest spoilage speed in catfish and hake, and the least speed in mackerel.

Preservación y abundancia de escamas de peces en sedimentos del margen continental de Chile (21-36° S Fish scale preservation and abundance in sediments from the continental margin off Chile (21-36° S

Directory of Open Access Journals (Sweden)

JAVIER A DÍAZ-OCHOA

2008-12-01

(Mo/Al, S/Al, Fe/Al using eight sediment cores taken from sites under the influence of the oxygen minimum zone off Chile (Iquique: 20°15' S, Mejillones Bay: 23° S, Concepción: 36° S. Off northern Chile (Iquique and Mejillones, fish scales from anchovy (Engraulis ringens and the Myctophidae family are dominant (mean = 90 and 120 scales 1,000 cm-3, respectively, whereas off central-southern Chile (Concepción, jack mackerel (Trachurus murphy scales are the most abundant (mean = 140 scales 1,000 cm-3. The abundance of hake (Merluccius gayi gayi and sardine (Sardinops sagax scales is approximately one order of magnitude lower than that of anchovy or jack mackerel. In general, the highest valúes and widest ranges of variation in the Mo/Al, S/Al, and Fe/Al ratios are found in Mejillones (Mo/Al ~ 0.8-12 mg g-1, S/Al 0.2-4.6 g g-1, Fe/Al 0.3-0.7 g g-1, followed by Iquique (Mo/Al ~ 0.2-1.8, S/Al 0.2-0.7, Fe/Al 0.5-0.8; Concepción has lower, less variable valúes (Mo/Al ~ 0.07, S/Al ~ 0.15, Fe/Al ~ 0.5. According to the Mo/Al ratio, used as an indicator of paleo-oxygenation, reducing conditions in the Mejillones Bay and Iquique sediments are relatively more intense than in those off Concepción. At all three sampling sites, the relationship between the abundance of anchovy scales and the logarithm of the Mo/Al ratio is statistically significant (r² = 0.46, P 1 mg g-1.

Toward a Profile of Soviet Behavior in International Financial Markets,

Science.gov (United States)

1987-08-01

duv. priding a hedge against both economic and political uncertaintv. l’oitical developments could cut oft Soviet access t(I Western credit marktt...deposits than heyc were paying on their loans, and this simple arbitrage operatio)n would have been p~rofitable. Opportunities for this kind of...8217 arbitrage miay’ hake persisted into 1985. when interest rates on short -term deposits finally% t’ell below the rates that the Soviet U nion would have been

At-Sea Hake Observer Program (ASHOP) Dataset - West Coast Groundfish Observer Program and At-Sea Hake Observer Program data collection, analysis and reporting

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Observer programs are the most comprehensive fishery dependent data collection system for total mortality estimation, protected species monitoring and discard data...

Ravintola konseptia etsimässä : Eksynyt Willi Hirvi

OpenAIRE

Mäntynen, Kaisu

2014-01-01

Opinnäytetyön tarkoituksena oli selvittää, millaisia palveluita Hotelli Jämsä Oy:n ravintolan Willi Hirven tulisi tarjota saadakseen toimintansa kannattavaksi. Ravintolan konsepti hakee suuntaansa, ja yritys halusi toiminnan suunnittelun avuksi tietoa palveluiden käyttäjiltä, sekä heiltä jotka eivät niitä käytä. Tutkimuksen kohteena olivat työnsä puolesta hotellissa majoittuvat asiakkaat ja paikalliset asukkaat, joita haluttaisiin palvella paremmin. Tutkimus oli otteeltaan kvalitatiivinen....

Fish allergy: evaluation of the importance of cross-reactivity.

Science.gov (United States)

Pascual, C; Martín Esteban, M; Crespo, J F

1992-11-01

Fish constitute one of the most important groups of allergens in the induction of immediate (type I) food hypersensitivity. In our environment, fish allergy is present in 22% of all patients with a diagnosis of food hypersensitivity. We studied the allergenic significance of the fish species considered most representative because of their greater consumption in our environment (flatfishes: Pleuronectiformes such as sole, whiff, and witch; Gadiformes such as hake; and Scombriformes such as albacore) or because of the results of previous studies of Gadiformes such as cod. Through the use of isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting, we have observed that several allergens common to all these species are able to bind specific IgE from the sera of sensitized patients. This allergenic community has been confirmed by radioallergosorbent inhibition. Another group of species-specific allergens focuses in the regions at about pH 5 and with molecular weights less than 14 kilodaltons; these allergens correspond to sarcoplasmic parvoalbumins. From the results observed, which have been confirmed by various procedures and techniques, we conclude that hake is the fish with the capability to induce the strongest IgE response, followed by whiff; the witch seems to be the least allergenic of all flatfishes. Among all species studied, albacore was the least allergenic. These results may be considered when one introduces supplementary feeding with fish in infants, most particularly in infants at high risk for atopy.

Sosiaalisen median rooli mikroyrittäjän ostoprosessissa

OpenAIRE

Martikainen, Inkeri

2014-01-01

Opinnäytetyön tavoite oli selvittää sosiaalisen median rooli mikroyrittäjän ostoprosessissa; miten mikroyrittäjä hakee tietoa sosiaalisesta mediasta ja millainen vaikutus sieltä löytyvillä käyttäjäarvioilla on ostopäätökseen. Opinnäytetyö tehtiin erään finanssialan yrityksen toimeksiantona. Opinnäytetyön tarkoituksena oli antaa digitaalisen markkinoinnin ammattilaisille tietoa siitä, miten mikroyrittäjiä voidaan tavoittaa sosiaalisen median kautta, ja saada näin uusia asiakkaita. Tutkimus...

Persistence and co-occurrence of demersal nurseries in the Strait of Sicily (central Mediterranean): Implications for fishery management

Science.gov (United States)

Garofalo, G.; Fortibuoni, T.; Gristina, M.; Sinopoli, M.; Fiorentino, F.

2011-08-01

This study investigated the nurseries of seven commercially important demersal species of the northern sector of the Strait of Sicily (central Mediterranean): red mullet, European hake, horned octopus, deep-water rose shrimp, greater forkbeard, Norway lobster and giant red shrimp. An eleven-year series of data collected through experimental trawling in the Strait of Sicily during spring and autumn was analyzed. The spatio-temporal persistence of the high-density aggregations (hot spots) of juvenile individuals in their first year of life was investigated to identify habitats that serve as nurseries. The density of recruits within the persistent nurseries was used as a proxy of the unit area contribution of individuals which recruit to the adult population. The spatial distribution patterns of the recruits of most the species were well defined and very stable in the long term. Persistent and potentially highly productive nurseries of European hake, deep-water rose shrimp and greater forkbeard were identified off the southern coast of Sicily. Persistent areas of recruits concentration were also observed for the other species investigated, but their specific potential contribution of individuals to the adult population was not substantial compared to adjacent grounds. The close or overlapped localization of sites which regularly host vulnerable life stages of different exploited species, revealed an area of great ecological significance which probably plays a major role in the dynamics of the fishery resources in the Strait of Sicily. Appropriate spatial protection measures of this area, including marine protected area designation, could complement conventional management approach for ensuring the long-term sustainability of these fisheries and stocks conservation.

On The improvement of physical and mechanical properties of PE by crosslinking

International Nuclear Information System (INIS)

Abbassi Souraki, F.; Morshedian, J.

2001-01-01

Improvement of PE properties has been carried out by several methods. In this work dicumyl peroxide was used for crosslinking of LDPE and bene improving the polymer properties. For sample preparation, an intensive mixing of polymer, peroxide and antioxidant in as Hake internal mixer at 110-115 d eg C was performed and followed by two-roll mixing. Finally process of crosslinking was conducted at 200 d eg C under 15 MPa pressure. After get content determination, tensile, DSc, DMTA and density tests were carried out on the samples. Results showed improved alterations in the properties

Changes in the northern Benguela ecosystem over three decades: 1970s, 1980s, and 1990s

DEFF Research Database (Denmark)

Heymans, J.J.; Shannon, L.J.; Jarre, Astrid

2004-01-01

The northern Benguela ecosystem has been overfished and physically challenged over the past three decades. Ecopath with Ecosim was used to construct three ecosystem models (1971-1977, 1980-1989, and 1990-1995) and to compare differences in ecosystem structure. In the 1970s, the system sustained...... existence. The importance of ecosystem-environmental interactions are highlighted by the abundance of horse mackerel, mesopelagics, small pelagics, and hake in the 1980s and the reduced biomass of most species in the 1990s, not only due to overfishing, but also due to the Benguela Nino that occurred in 1995...

Levels of total mercury in marine organisms from Adriatic Sea, Italy.

Science.gov (United States)

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Zaccaroni, Annalisa; Olivieri, Vincenzo; Amorena, Michele

2009-08-01

The presence of total mercury in fish, crustacean and cephalopod from Adriatic Sea, was investigated. The highest concentrations were observed in decreasing order in: Norway lobster (0.97 +/- 0.24 mg/kg; mean +/- SE), European hake (0.59 +/- 0.14 mg/kg), red mullet (0.48 +/- 0.09 mg/kg), blue whiting (0.38 +/- 0.09 mg/kg), Atlantic mackerel (0.36 +/- 0.08 mg/kg) and European flying squid (0.25 +/- 0.03 mg/kg). A significant difference (p fish and fishery products can exceed the maximum levels and stress the need of more information for consumers in particular for people that eat large amount of fish.

Use of commercial vessels in survey augmentation: the size-frequency distribution

Directory of Open Access Journals (Sweden)

Eric N. Powell

2006-09-01

Full Text Available The trend towards use of commercial vessels to enhance survey data requires assessment of the advantages and limitations of various options for their use. One application is to augment information on size-frequency distributions obtained in multispecies trawl surveys where stratum boundaries and sampling density are not optimal for all species. Analysis focused on ten recreationally and commercially important species: bluefish, butterfish, Loligo squid, weakfish, summer flounder, winter flounder, silver hake (whiting, black sea bass, striped bass, and scup (porgy. The commercial vessel took 59 tows in the sampled domain south of Long Island, New York and the survey vessel 18. Black sea bass, Loligo squid, and summer flounder demonstrated an onshore-offshore gradient such that smaller fish were caught disproportionately inshore and larger fish offshore. Butterfish, silver hake, and weakfish were characterized by a southwest-northeast gradient such that larger fish were caught disproportionately northeast of the southwestern-most sector. All sizes of scup, striped bass, and bluefish were caught predominately inshore. Winter flounder were caught predominately offshore. The commercial vessel was characterized by an increased frequency of large catches for most species. Consequently, patchiness was assayed to be higher by the commercial vessel in nearly all cases. The size-frequency distribution obtained by the survey vessel for six of the ten species, bluefish, butterfish, Loligo squid, summer flounder, weakfish, and silver hake, could not be obtained by chance from the size-frequency distribution obtained by the commercial vessel. The difference in sample density did not significantly influence the size-frequency distribution. Of the six species characterized by significant differences in size-frequency distribution between boats, all but one was patchy at the population level and all had one or more size classes so characterized. Although the

Overfishing of small pelagic fishes increases trophic overlap between immature and mature striped dolphins in the Mediterranean Sea.

Science.gov (United States)

Gómez-Campos, Encarna; Borrell, Assumpció; Cardona, Luis; Forcada, Jaume; Aguilar, Alex

2011-01-01

The interactions among diet, ecology, physiology, and biochemistry affect N and C stable isotope signatures in animal tissues. Here, we examined if ecological segregation among animals in relation to sex and age existed by analyzing the signatures of δ(15)N and δ(13)C in the muscle of Western Mediterranean striped dolphins. Moreover, we used a Bayesian mixing model to study diet composition and investigated potential dietary changes over the last two decades in this population. For this, we compared isotope signatures in samples of stranded dolphins obtained during two epizootic events occurring in 1990 and 2007-2008. Mean δ(13)C values for females and males were not significantly different, but age-related variation indicated δ(13)C enrichment in both sexes, suggesting that females and males most likely fed in the same general areas, increasing their consumption of benthic prey with age. Enrichment of δ(15)N was only observed in females, suggesting a preference for larger or higher trophic level prey than males, which could reflect different nutritional requirements. δ(13)C values showed no temporal variation, although the mean δ(15)N signature decreased from 1990 to 2007-2008, which could indicate a dietary shift in the striped dolphin over the last two decades. The results of SIAR indicated that in 1990, hake and sardine together contributed to 60% on the diet of immature striped dolphins, and close to 90% for mature striped dolphins. Conversely, the diet of both groups in 2007-2008 was more diverse, as hake and sardine contributed to less than 40% of the entire diet. These results suggest a dietary change that was possibly related to changes in food availability, which is consistent with the depletion of sardine stocks by fishing.

Advances on the molecular characterization, clinical relevance, and detection methods of Gadiform parvalbumin allergens.

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Fernandes, Telmo J R; Costa, Joana; Carrapatoso, Isabel; Oliveira, Maria Beatriz P P; Mafra, Isabel

2017-10-13

Gadiform order includes several fish families, from which Gadidae and Merlucciidae are part of, comprising the most commercially important and highly appreciated fish species, such as cod, pollock, haddock, and hake. Parvalbumins, classified as calcium-binding proteins, are considered the main components involved in the majority of fish allergies. Nine and thirteen parvalbumins were identified in different fish species from Gadidae and Merlucciidae families, respectively. This review intends to describe their molecular characterization and the clinical relevance, as well as the prevalence of fish allergy. In addition, the main protein- and DNA-based methods to detect fish allergens are fully reviewed owing to their importance in the safeguard of sensitized/allergic individuals.

Use of seasonal freshwater wetlands by fishes in a temperate river floodplain

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Henning, Julie A.; Gresswell, Robert E.; Fleming, Ian A.

2007-01-01

This study examined the use of freshwater wetland restoration and enhancement projects (i.e. non-estuarine wetlands subject to seasonal drying) by fish populations. To quantify fish use of freshwater emergent wetlands and assess the effect of wetland enhancement (i.e. addition of water control structures), two enhanced and two unenhanced emergent wetlands were compared, as well as two oxbow habitats within the Chehalis River floodplain. Eighteen fish species were captured using fyke nets and emigrant traps from January to the beginning of June, with the most abundant being three-spined stickleback Gasterosteus aculeatus and Olympic mudminnow Novumbra hubbsi. Coho salmon Oncorhynchus kisutch was the dominant salmonid at all sites. Enhanced wetlands, with their extended hydroperiods, had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Both enhanced and unenhanced emergent wetlands yielded higher abundances of non-game native fishes than oxbow habitats. Oxbow habitats, however, were dominated by coho salmon. Fish survival in the wetland habitats was dependent on emigration to the river before dissolved oxygen concentrations decreased and wetlands became isolated and stranding occurred. This study suggests that wetland enhancement projects with an outlet to the river channel appear to provide fishes with important temporary habitats if they have the opportunity to leave the wetland as dissolved oxygen levels deteriorate.

Research into aroma changes in irradiated foodstuffs. I.- Studies on Fish

International Nuclear Information System (INIS)

Barrero Pinero, R.; Gasco Sanchez, L.; Valverde Garcia, F.

1972-01-01

Radiolytic formation of volatile compounds have been investigated in fillets of hake, codfish and bonito gamma-irradiated at a dose range of 0.1-5 Mrads. Analytical methods have been developed by gas chromatography of functional group derivatives: carbonyls as 2,4,-dinitrophenyl hydrazones, primary and secondary amines as N-alkyl benzamides, and thiols as 2,4-dinitrophenyl alkyl thioethers. The main results are as follows: increasing with the integral dose of the whole carbonyls, the most significant components being acetaldehyde, propional dehyde and formaldehyde; no significant variations with the integral dose od the traces of ammonia, methylamine, trimethylamine, ethylamine, diethylamine, propylamine, butylamine and pentylamine found in unirradiated samples; and radiolytic formation of methanethiol and dimethyl disulfide. (Author) 98 refs

Research into aroma changes in irradiated foodstuffs. I.- Studies on Fish; Investigacion de Alteraciones de Aroma en alimentos irradiados. I Estudio sobre Pescado

Energy Technology Data Exchange (ETDEWEB)

Barreiro Pinero, R; Gasco Sanchez, L; Valverde Garcia, F

1972-07-01

Radiolytic formation of volatile compounds have been investigated in fillets of hake, codfish and bonito gamma-irradiated at a dose range of 0.1-5 Mrads. Analytical methods have been developed by gas chromatography of functional group derivatives: carbonyls as 2,4,-dinitrophenyl hydrazones, primary and secondary amines as N-alkyl benzamides, and thiols as 2,4-dinitrophenyl alkyl thioethers. The main results are as follows: increasing with the integral dose of the whole carbonyls, the most significant components being acetaldehyde, propional dehyde and formaldehyde; no significant variations with the integral dose od the traces of ammonia, methylamine, trimethylamine, ethylamine, diethylamine, propylamine, butylamine and pentylamine found in unirradiated samples; and radiolytic formation of methanethiol and dimethyl disulfide. (Author) 98 refs.

Descripción de la pesquería artesanal de peces, en tres puertos pesqueros de la IV región, Coquimbo, Chile.

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Rigoberto Víquez Portuguez

2016-03-01

Full Text Available Se realizó un seguimiento de la pesca artesanal de peces en las caletas de Coquimbo, Guanaqueros y Tongoy en la IV región, Chile, entre junio de 1995 y junio de 1996. El estudio comprendió un análisis de las especies capturadas , biomasa de ellas, artes de pesca empleadas y desembarque en cada caleta por medio de formularios acordados en un proyecto convenio tripartito entre la Federación de Trabajadores del Mar (FETRAMAR de la provincia de Elqui F.G., el Servicio Nacional de Pesca de la IV región (SERNAP y la Universidad Católica del Norte (UCN. Se capturó un total de 27 especies de interés comercial y las especies de mayor relevancia fueron la anchoveta (Engraulis ringens y el jurel (Trachurus murphyi, capturadas con red de cerco; la merluza (Merluccius gayi y la reineta (Brama austalis capturadas con espinel.

Partial purification and characterization of cysteine proteinase inhibitor from chicken plasma.

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Rawdkuen, Saroat; Benjakul, Soottawat; Visessanguan, Wonnop; Lanier, Tyre C

2006-08-01

A high-molecular-weight cysteine proteinase inhibitor (CPI) was purified from chicken (Gallus gallus) plasma using polyethylene glycol (PEG) fractionation and affinity chromatography on carboxymethyl-papain-Sepharose-4B. The CPI was purified 96.8-fold with a yield of 28.9%. Based on inhibitory activity staining for papain, CPI was shown to have an apparent molecular mass of 122 kDa. No inhibitory activity was obtained under reducing condition, indicating that CPI from chicken plasma was stabilized by disulfide bonds. CPI was stable in temperature ranges from 40 to 70 degrees C for 10 min; however, more than 50% of the inhibitory activity towards papain was lost within 30 min of heating at 90 degrees C. CPI was stable in the presence of salt up to 3%. The purified CPI exhibited the inhibitory activity toward autolysis of arrowtooth flounder (Atheresthes stomias) and Pacific whiting (Merluccius productus) natural actomyosin (NAM) in a concentration-dependent manner.

The fish and fisheries of Jones Bank and the wider Celtic Sea

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Martinez, I.; Ellis, J. R.; Scott, B.; Tidd, A.

2013-10-01

The Celtic Sea is a diverse fishing ground that supports important commercial fisheries for a range of demersal fish, large and small-bodied pelagic fish and a variety of cephalopods and other shellfish. A regional overview of the main commercial fish stocks of the Celtic Sea and of the fish that occur in the vicinity of Jones Bank are provided through analyses of landings data from English and Welsh vessels, and from scientific trawl surveys. Dedicated smaller scale sampling via trawl surveys combined with baited cameras on and around the Jones Bank were also analysed to investigate the importance of sandbank habitats with attention paid to the differences in the species occurring on the top of the bank in comparison to adjacent off-bank habitats. Official landing statistics for UK (English and Welsh) vessels indicated that the predominant commercial demersal species in ICES Divisions VIIg,h (in terms of quantities landed) were anglerfish, megrim, pollack and skates (Rajidae). There were, however, regional differences in the distribution of fish and fisheries, and the area surrounding Jones Bank (ICES Rectangles 28E1 and 28E2) supports fisheries for megrim, anglerfish, skates, hake, ling and turbot, with otter trawl, gillnet and beam trawl the main gears used. Recent survey data collected with GOV (Grande Ouverture Verticale) trawl from the Celtic Sea (ICES Divisions VIIe-h, 2007-2010) were used to highlight the broad scale distribution of the main fish assemblages in the Celtic Sea. Analyses of the fish and cephalopod catches from these surveys indicated that there were four broad assemblages in the area, including (i) a region around the Cornwall (which will also be partly influenced by the necessity to use rockhopper ground gear on these rough grounds), (ii) the shallower regions of the north-western Celtic Sea (including parts of the Bristol Channel), (iii) the deeper parts of the outer shelf and (iv) the central Celtic Sea. These data also provided

Impacts of curricular change: Implications from 8 years of data in introductory physics

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Pollock, Steven J.; Finkelstein, Noah

2013-01-01

Introductory calculus-based physics classes at the University of Colorado Boulder were significantly transformed beginning in 2004. They now regularly include: interactive engagement using clickers in large lecture settings, Tutorials in Introductory Physics with use of undergraduate Learning Assistants in recitation sections, and a staffed help-room setting where students work on personalized CAPA homework. We compile and summarize conceptual (FMCE and BEMA) pre- and post-data from over 9,000 unique students after 16 semesters of both Physics 1 and 2. Within a single institution with stable pre-test scores, we reproduce results of Hake's 1998 study that demonstrate the positive impacts of interactive engagement on student performance. We link the degree of faculty's use of interactive engagement techniques and their experience levels on student outcomes, and argue for the role of such systematic data collection in sustained course and institutional transformations.

Detection of Different DNA Animal Species in Commercial Candy Products.

Science.gov (United States)

Muñoz-Colmenero, Marta; Martínez, Jose Luis; Roca, Agustín; Garcia-Vazquez, Eva

2016-03-01

Candy products are consumed all across the world, but there is not much information about their composition. In this study we have used a DNA-based approach for determining the animal species occurring in 40 commercial candies of different types. We extracted DNA and performed PCR amplification, cloning and sequencing for obtaining species-informative DNA sequences. Eight species were identified including fish (hake and anchovy) in 22% of the products analyzed. Bovine and porcine were the most abundant appearing in 27 samples each one. Most products contained a mixture of species. Marshmallows (7), jelly-types, and gummies (20) contained a significantly higher number of species than hard candies (9). We demonstrated the presence of DNA animal species in candy product which allow consumers to make choices and prevent allergic reaction. © 2016 Institute of Food Technologists®

Evaluating learning and teaching using the Force Concept Inventory

Science.gov (United States)

Zitzewitz, Paul

1997-04-01

Teaching methods used in the calculus-based mechanics course for engineers and scientists (P150) at the University of Michigan-Dearborn were markedly changed in September, 1996. Lectures emphasize active learning with Mazur's ConcepTests, Sokoloff's Interactive Demonstrations, and Van Heuvelen's ALPS Kit worksheets. Students solve context-rich problems using Van Heuvelen's multiple representation format in cooperative groups in discussion sections. Labs were changed to use MBL emphasizing concepts and Experiment Problems to learn lab-based problem solving. Pre- and post-testing of 400 students with the Force Concept Inventory has demonstrated considerable success. The average increase in score has been 35-45methods as defined by Hake. The methods and results will be discussed. Detailed analyses of the FCI results will look at success in teaching specific concepts and the effect of student preparation in mathematics and high school physics.

Larval fish distribution and their relationship with environmental factors in the southern Tyrrhenian Sea (central Mediterranean during two years of sampling

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Adriana Profeta

2014-06-01

The results of this study could have implications for the management of marine resources, because the investigated area has already been identified as a nursery area for many pelagic and coastal fishes and a natural habitat for many species of high commercial interest. Fig. 1. Results of CCA analysis for larval fish species and sampled stations during June 2006. Two first axes (CCA1 and CCA2 are represented. Species abbreviations in alphabetical order: An_a (Anthias anthias, Ap_i (Apogon imberbis, Ar_k (Arnoglossus kessleri, Ar_h (Argyropelecus hemigymnus, Ar_l (Arnoglossus laterna, Ar_r (Arnoglossus rueppelii, Ar_t (Arnoglossus thori, Be_g (Benthosema glaciale, Bl_o (Blennius ocellaris, Bo_b (Boops boops, Bo_p (Bothus podas, Ca_a (Capros aper, Ca_p (Callyonimus maculatus, Ce_m (Ceratoscopelus maderensis, Ce_m1(Cepola macrophtalma, Ci_l (Citharus linguatula, Co_j (Coris julis, Co_n (Ophidion barbatum, Cy_b (Cyclothone braueri, Cy_p (Cyclothone pygmaea, En_e (Engraulis encrasicolus, Di_a (Diplodus annularis, Di_h (Diaphus holti, Di_r (Diaphus rafinesquei, El_r (Electrona rissoi, Go_n (Gobius niger, He_d (Helicolenus dactylopterus, Hy_b (Hygophum benoiti, Hy_h (Hygophum hygomii, La_c (Lampanyctus crocodilus, La_p (Lampanyctus pusillus, Le_c (Lepidotrigla cavillone, Le_j (Lestidiops jayakari, Lo_d (Lobianchia dofleini, Ma_m (Maurolicus muelleri, Ma_s (Macrorhamphosus scolopax, Me_m (Merluccius merluccius, Mi_p (Micromesistius poutassou, My_p (Myctophum punctatum, Mu_s (Mullus surmuletus, Ne_s (Nemichthys scolopaceus, No_b (Notoscopelus bolini, No_e (Notoscopelus elongatus, No_r (Arctozenus risso, Ob_m (Oblada melanura, Pa_s (Paralepis speciosa. Sc_p (Scorpaena porcus, Sc_s (Scorpaena scrofa, Se_c (Serranus cabrilla, Se_h (Serranushepatus, Sp_f (Spicara maena, Sp_s (Spicara smaris, Sy sp. (Symphurus nigrescens, Sy_v, (Symphurus ligulatus, St_b (Stomias boa boa, Tr_d (Trachinus draco, Tr_me (Trachurus mediterraneus, Tr_t (Trachurus trachurus, Ur_s (Uranoscopus scaber

Human exposure to lead, cadmium and mercury through fish and seafood product consumption in Italy: a pilot evaluation.

Science.gov (United States)

Pastorelli, A A; Baldini, M; Stacchini, P; Baldini, G; Morelli, S; Sagratella, E; Zaza, S; Ciardullo, S

2012-01-01

The presence of selected toxic heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg), was investigated in fish and seafood products, namely, blue mussel, carpet shell clam, European squid, veined squid, deep-water rose shrimp, red mullet, European seabass, gilthead seabream, Atlantic cod, European hake, Atlantic bluefin tuna and swordfish so as to assess their human exposure through diet. Metals were detected by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and hydride generation atomic absorption spectrometry (Hg-AAS). Measurements of Cd, Pb and Hg were performed by means of analytical methods validated in compliance with UNI CEI EN ISO/IEC 17025 [2005. General requirements for the competence of testing and calibration laboratories. Milano (Italy): UNI Ente Nazionale Italiano di Unificazione]. The exposure assessment was undertaken matching the levels of Cd, Pb and total Hg with consumption data related to fish and seafood products selected for this purpose. In order to establish human health implications, the estimated weekly intakes (EWIs) for Cd, Pb and Hg were compared with the standard tolerable weekly intakes (TWI) for Cd and provisional tolerable weekly intakes (PTWIs) for Pb and Hg stipulated by the European Food Safety Authority (EFSA) and the Food and Agriculture Organization/World Health Organization (FAO/WHO) Joint Expert Committee on Food Additives (JECFA). The found metal concentrations were largely below the maximum levels (MLs) established at the European Union level with the exception of Cd. This metal exceeded the MLs in squid, red mullet, European hake and Atlantic cod. Squid and blue mussel showed the highest Pb concentrations which accounted for 60% and 10% of the MLs, respectively. Highest Hg levels were found in predatory fish. The concentrations of Hg in swordfish, Atlantic bluefin tuna and red mullet accounted for 50%, 30% and 30% of the MLs, respectively. The EWIs for Cd, Pb and Hg related to the consumption

Interdisciplinary Program For In-Service Teachers; Working with Industry And University to Enhance Learning Experiences in the State of Ohio (Invited Paper

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Suzanne Lunsford

2014-12-01

Full Text Available Science Teaching for Ohio's New Economy (STONE is an interdisciplinary professional development program that inservice teachers grades K-12 that experience the integration of earth and physical science in an inquiry-based field. There are various field trips to various industrial settings that teach how geoscientist works in the aggregate industry. During the academic year there is a support system where the industry and the in-service teachers engage their students into real world industrial applications in the aggregate industry. This paper will discuss the utilization of high – tech instrumentation such as X-Ray Fluorescence and Scanning Electron Microscopy to teach real-world science applications of concern. Pre- and Post-test assessments as addressed by R.R. Hake have shown that these inquirybased professional development workshops that integrated academia with industry as a positive outcome for our students in Ohio.

Software Process Modeling and Execution within Virtual Environments

Science.gov (United States)

1997-08-01

LhFEX@nOHX@nOe+L X@L X[Lhq³AKe.?HWLvJ&%HV,=>brP"sK\\QehJQFK\\QH�X@nOehJQuUJQehJQHWLe.=�RaHnX>V.VhJQHWY�=@seR³ qwe .?H"L.X>PH?³sP[X>ApX>SUHA...HWLhe.HWYðR³ qwe .?H"YKHWL.nOVhJQFehJQ=@Aº=>bX>VoehJcb X@nOeOLiX>RE=>u@H@IÛe.?H?KsP�X>AºX>S@HAKe+LJQAºe.?HFV.=nOHWL.LX>V.HV.HFV.H� LhH...EX@LiLhsReOX@LhGLCr�’?H ÊUÇ�ÅÄWÀEÕUÄ+Õ,Lhe+Xke.HYUJMY A=@e,nO=@V.V.HWLlFE=@AEY�e.=�XkA³ qwe +XULhGÙIX>AEY�Lh=JQe,giX@L’VoHP=>u@HWYC

Enseñanza de las leyes de Newton en grado décimo bajo la Metodología de Aprendizaje Activo

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Jholman Andres Moreno

2017-07-01

Full Text Available Este documento presenta los resultados de la implementación de la unidad didáctica para la enseñanza de las leyes de Newton bajo la Metodología de Aprendizaje Activo en el grado 10-6 en la Institución Educativa Colegio Departamental La Esperanza de Villavicencio.  La metodología empleada fue la Investigación Acción, basada en cuatro pilares fundamentales: planear, actuar, observar y reflexionar, proceso cíclico que busca desde la interpretación de un aspecto social producir un cambio positivo de orden social. Para evaluar la efectividad de la unidad didáctica, se utilizó el factor de Hake,  para ello se analizan los resultados del pre test y el post-test, encontrándose que ésta  tuvo una ganancia de aprendizaje conceptual o ganancia relativa media.

Estado de conservación de los peces de la familia Goodeidae (Cyprinodontiformes en la mesa central de México

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Marina Y De la Vega-Salazar

2006-03-01

Full Text Available Se estableció el estado de conservación y se identificaron los riesgos que presentan los peces de la familia Goodeidae en la Mesa Central de México. Para ello se evaluó la disminución en el número de localidades y el área de distribución, y se incorporó una descripción limnológica en 53 localidades. Esta evaluación incluyó una comparación de las colecciones actuales con registros hist��ricos de la distribución de la familia. Un análisis de componentes principales de las variables limnológicas indicó que la mayoría de las especies de goodeidos habitan localidades caracterizadas por tener poca degradación ambiental, y sólo pocas especies parecen tener elevada tolerancia a dicho estado de contaminación. Los resultados de la disminución histórica de localidades y del área de distribución sugieren que el estado de conservación de las especies (de acuerdo con los criterios de la IUCN es el siguiente: una especie está extinta (Allotoca catarinae, una especie está extinta en la naturaleza (Skiffia francesae, ya que existen ejemplares en cautiverio, ocho están en peligro crítico (Allotoca goslinei, Allotoca regalis, Allotoca zacapuensis, Allodontichthys hubbsi, Ameca splendens, Characodon audax, Hubbsina turneri y Zoogoneticus tequila, once están en peligro, ocho se consideran como vulnerables, cuatro se pueden considerar en riesgo próximo y sólo dos parecen no enfrentar ningún riesgo. En conclusión, la pérdida de hábitat, la introducción de especies exóticas de peces, el ámbito geográfico restringido y la especialización ecológica de las especies son los principales factores de riesgo para las especies estudiadas de la familia Goodeidae. La supervivencia de este grupo requiere acciones para su conservación.Conservation status of Goodeidae familiy fishes (Cyprinodontiformes from the Mexican Central Plateau. To establish the conservation status and threats for Goodeidae fishes in the high plateau of Mexico

Correlation researches of the outgoing directions 'shake-off' electron and positron at β+ - decay

International Nuclear Information System (INIS)

Mitrokhovich, N.F.; Kupryashkin, V.T.; Sidorenko, L.P.

2012-01-01

The correlation properties electron 'shake-off' at β + -decay is studied. The measurements were fulfilled in compare with such properties 'shake-off' electron at β - -decay for explanation mechanism, accountable for correlation motion 'shake-off' electron and main particle (electron at β'--decay and positron at β + -decay). 152 Eu decay was used for it. The measurements were performed on the installation of coincidences of γ-quanta with electrons and low energy electrons, including of e 0 -electrons of the secondary electron emission (γγee 0 -coincidences). The registration of electrons 'shake-off' implemented on e 0 -electrons, created by them. On obtained data, the space correlation of electron 'shake-off' with positron at β + -decay in direction forward is much less that those correlating s hake-off - electron at β - -decay. 'Shake-off'-electrons at β + -decay are predominantly moving in large solid angles relate positron. The mechanism, accountable for it, is proposed

Quality loss assessment in fish-based ready-to-eat foods during refrigerated storage

Energy Technology Data Exchange (ETDEWEB)

Pourashouri, P.; Chapela, M. J.; Atanassova, M.; Cabado, A. G.; Vieites, J. M.; Aubourg, S. P.

2013-05-01

The present research addresses the quality loss in two different ready-to-eat (RTE) sea foods. With this aim, chemical and microbiological parameters were measured in tuna lasagne (TL) and hake roe foods which were refrigerated (4 degree centigrade) for up to 35 and 71 days, respectively. Both foods showed a significant lipid oxidation (peroxide and interaction compound formation) development with storage time, which was especially marked in the case of the TL product, which also underwent an important lipid hydrolysis development. Both RTE products showed a low microbial development, no matter how much time had elapsed since the expiration dates; thus, low total viable count scores and volatile amine formation were attained while the presence of pathogen microorganisms was not detected. In view of the current increasing consumer demand for high quality refrigerated foods, the assessment of lipid damage related to nutritional and sensory values is recommended when fish-based RTE products are encountered. (Author) 46 refs.

Basing assessment and treatment of problem behavior on behavioral momentum theory: Analyses of behavioral persistence.

Science.gov (United States)

Schieltz, Kelly M; Wacker, David P; Ringdahl, Joel E; Berg, Wendy K

2017-08-01

The connection, or bridge, between applied and basic behavior analysis has been long-established (Hake, 1982; Mace & Critchfield, 2010). In this article, we describe how clinical decisions can be based more directly on behavioral processes and how basing clinical procedures on behavioral processes can lead to improved clinical outcomes. As a case in point, we describe how applied behavior analyses of maintenance, and specifically the long-term maintenance of treatment effects related to problem behavior, can be adjusted and potentially enhanced by basing treatment on Behavioral Momentum Theory. We provide a brief review of the literature including descriptions of two translational studies that proposed changes in how differential reinforcement of alternative behavior treatments are conducted based on Behavioral Momentum Theory. We then describe current clinical examples of how these translations are continuing to impact the definitions, designs, analyses, and treatment procedures used in our clinical practice. Copyright © 2017 Elsevier B.V. All rights reserved.

Influence of Electron Molecule Resonant Vibrational Collisions over the Symmetric Mode and Direct Excitation-Dissociation Cross Sections of CO2 on the Electron Energy Distribution Function and Dissociation Mechanisms in Cold Pure CO2 Plasmas.

Science.gov (United States)

Pietanza, L D; Colonna, G; Laporta, V; Celiberto, R; D'Ammando, G; Laricchiuta, A; Capitelli, M

2016-05-05

A new set of electron-vibrational (e-V) processes linking the first 10 vibrational levels of the symmetric mode of CO2 is derived by using a decoupled vibrational model and inserted in the Boltzmann equation for the electron energy distribution function (eedf). The new eedf and dissociation rates are in satisfactory agreement with the corresponding ones obtained by using the e-V cross sections reported in the database of Hake and Phelps (H-P). Large differences are, on the contrary, found when the experimental dissociation cross sections of Cosby and Helm are inserted in the Boltzman equation. Comparison of the corresponding rates with those obtained by using the low-energy threshold energy, reported in the H-P database, shows differences up to orders of magnitude, which decrease with the increasing of the reduced electric field. In all cases, we show the importance of superelastic vibrational collisions in affecting eedf and dissociation rates either in the direct electron impact mechanism or in the pure vibrational mechanism.

The use of Pb-210/Ra-226 and Th-228/Ra-228 dis-equilibria in the ageing of otoliths of marine fish

International Nuclear Information System (INIS)

Smith, J.N.; Nelson, R.; Campana, S.E.

1991-01-01

Naturally-occurring isotopes of radium are ideally suited as tracers for chemical uptake in the calcified tissues of marine organisms since radium is a water soluble, bio-geochemical analogue for calcium. Assays designed to exploit this uptake mechanism can be used to determine the longevity of certain species of fish. Measurements of Pb-210/Ra-226 disequilibria in the otoliths of redfish have revealed that this species of fish can live to ages in excess of 75 years in coastal waters off Nova Scotia, Canada. Measurements of the Th-228/Ra-228 disequilibria in the otoliths of the much shorter-lived silver hake and flying fish may provide estimates of longevity on time scales of 0-10 years, which could then be used to evaluate the accuracy of currently-used ageing models based on otolith annulus counts. Age determinations of fish based on natural radioisotopes can result in significant improvements in the assessment and management of certain fisheries resources. (author)

Seating Arrangement, Group Composition and Competition-driven Interaction: Effects on Students' Performance in Physics

International Nuclear Information System (INIS)

Roxas, R. M.; Monterola, C.; Carreon-Monterola, S. L.

2010-01-01

We probe the effect of seating arrangement, group composition and group-based competition on students' performance in Physics using a teaching technique adopted from Mazur's peer instruction method. Ninety eight lectures, involving 2339 students, were conducted across nine learning institutions from February 2006 to June 2009. All the lectures were interspersed with student interaction opportunities (SIO), in which students work in groups to discuss and answer concept tests. Two individual assessments were administered before and after the SIO. The ratio of the post-assessment score to the pre-assessment score and the Hake factor were calculated to establish the improvement in student performance. Using actual assessment results and neural network (NN) modeling, an optimal seating arrangement for a class was determined based on student seating location. The NN model also provided a quantifiable method for sectioning students. Lastly, the study revealed that competition-driven interactions increase within-group cooperation and lead to higher improvement on the students' performance.

How well can fishes prey on zebra mussels in eastern North America?

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French, John R. P.

1993-01-01

Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations of drum, sunfishes and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

Evaluación del estado del stock de merluza (Merluccius gayi peruanus Ginsburg) en el mar peruano. 2008

OpenAIRE

Lassen, Hans; Barriga Rivera, Edward; Palacios León, Jacqueline; Vargas López, Nathaly; Díaz Acuña, Erich; Argüelles Torres, Juan

2009-01-01

Análisis del estado del stock de la merluza peruana, mediante un análisis de población virtual, haciendo uso de la información disponible en la Unidad de Investigaciones en Peces Demersales, Bentónicos y Litorales (UIPDBL) del Instituto del Mar del Perú (IMARPE), actualizada y revisada a partir de la información empleada en los paneles de expertos precedentes (2003 y 2004). Boletín IMARPE vol. 24 nº 1-2, 2009; p. 21-26

Effect of frying, grilling, and steaming on amino acid composition of marine fishes.

Science.gov (United States)

Erkan, Nuray; Özden, Özkan; Selçuk, Arif

2010-12-01

Amino acid and proximate compositions were determined in six raw and cooked marine fish species that are commonly consumed in Turkey. The changes in amino acid and proximate content were found to be significant for all cooking methods in all fish species. Cooking did, in general, significantly increase the contents of essential, semiessential, and other amino acids compared with raw fish species. Grilled Atlantic bonito, anchovy, and bluefish and fried mullet and hake appeared to be more valuable fish dishes for obtaining the officially recommended appropriate daily intake of essential amino acids for humans. Moisture, fat, ash, and carbohydrate contents of raw fish ranged between 48.01% and 83.05%, 0.87% and 30.48%, 1.10% and 1.61%, and 0.09% and 8.70%, respectively. All fresh fish investigated were high in protein: 11.20-17.14 g/100 g. Wide variations in protein content (18.11-25.65 g/100 g) between species and methods of cooking were observed. Fried fish had intermediate fat values, whereas grilled and steamed fishes had a comparatively low value.

Will the No Child Left Behind Act Promote Direct Instruction of Science?

Science.gov (United States)

Hake, Richard

2005-03-01

Education research in physics at the high school and undergraduate level strongly suggests that interactive engagement enhances students' conceptual understanding much more than traditional Direct Science Instruction (DSI). Similar conclusions can be drawn from K-8 science-education research. Nevertheless, DSI predominates in CA because of the DSI- orientation of the CA State Board of Education and Curriculum Commission [1]. Likewise the U.S. Dept. of Education's (USDE's): (a) DSI-orientation as demonstrated by its recent national-education summit showcasing of the research of Klahr and Nigam [2]; and (b) science achievement testing starting in 2007; threatens to promote DSI nationwide. It might be hoped that NRC's expert science education committees will steer the USDE away from promoting DSI, the antithesis of the NRC's own recommendations for inquiry methods. [1] R.R. Hake. ``Direct Science Instruction Suffers a Setback in California - Or Does It?" (2004), pdf>. [2] Klahr, D. & M. Nigam. 2004. ``The equivalence of learning paths in early science instruction: effects of direct instruction and discovery learning" (2004), .

Analysis Dataset - West Coast Groundfish Observer Program and At-Sea Hake Observer Program data collection, analysis and reporting

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Observer programs are the most comprehensive fishery dependent data collection system for total mortality estimation, protected species monitoring and discard data...

Learning to Work with Databases in Astronomy: Quantitative Analysis of Science Educators' and Students' Pre-/Post-Tests

Science.gov (United States)

Schwortz, Andria C.; Burrows, Andrea C.; Myers, Adam D.

2015-01-01

Astronomy is increasingly moving towards working with large databases, from the state-of-the-art Sloan Digital Sky Survey Data Release 10, to the historical Digital Access to a Sky Century at Harvard. Non-astronomy fields as well tend to work with large datasets, be it in the form of warehouse inventory, health trends, or the stock market. However very few fields explicitly teach students the necessary skills to analyze such data. The authors studied a matched set of 37 participants working with 200-entry databases in astronomy using Google Spreadsheets, with limited information about a random set of quasars drawn from SDSS DR5. Here the authors present the quantitative results from an eight question pre-/post-test, with questions designed to span Bloom's taxonomy, on both the topics of the skills of using spreadsheets, and the content of quasars. Participants included both Astro 101 summer students and professionals including in-service K-12 teachers and science communicators. All groups showed statistically significant gains (as per Hake, 1998), with the greatest difference between women's gains of 0.196 and men's of 0.480.

Designing experiments on thermal interactions by secondary-school students in a simulated laboratory environment

Science.gov (United States)

Lefkos, Ioannis; Psillos, Dimitris; Hatzikraniotis, Euripides

2011-07-01

Background and purpose: The aim of this study was to explore the effect of investigative activities with manipulations in a virtual laboratory on students' ability to design experiments. Sample Fourteen students in a lower secondary school in Greece attended a teaching sequence on thermal phenomena based on the use of information and communication technology, and specifically of the simulated virtual laboratory 'ThermoLab'. Design and methods A pre-post comparison was applied. Students' design of experiments was rated in eight dimensions; namely, hypothesis forming and verification, selection of variables, initial conditions, device settings, materials and devices used, process and phenomena description. A three-level ranking scheme was employed for the evaluation of students' answers in each dimension. Results A Wilcoxon signed-rank test revealed a statistically significant difference between the students' pre- and post-test scores. Additional analysis by comparing the pre- and post-test scores using the Hake gain showed high gains in all but one dimension, which suggests that this improvement was almost inclusive. Conclusions We consider that our findings support the statement that there was an improvement in students' ability to design experiments.

Comparative study of nutritional constituents and the mercury total constituents in fishes commercialized at the city of Cananeia, at the coastal of Sao Paulo, Brazil

International Nuclear Information System (INIS)

Nascimento, Soraia M.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Deborah I.T.; Braga, Elisabete S.

2009-01-01

Aiming the determination of the Hg concentration and the As, Cr and Zn trace elements, four commercial available and frequently consumable fishes by the Cananeia, Sao Paulo, Brazil, were analysed. A total of 53 samples were evaluated as follows: jew fish (Micropogonias furnieri), hake (Macrodon ancylodon), perch (Centropomus undecimalis), and grey mullet (Mugil platanus), all acquired at local fishmonger. The atomic absorption and neutron activation analysis techniques were used for the determination of Hg total levels and trace elements respectively. The trace elements presented large concentration variation among the same specie and the species performed as well. The jew fish presented levels superior to 1000 μg kg -1 for the most individuals analysed and the perch presented chromium levels exceeding the limit of 0.10 mg kg -1 for some individuals. The level of Zn presented values below 50 mg kg -1 established by the Brazilian legislation for all species. The Zn total contents among all species presented values bellow the limits of the Brazilian legislation (500 μg kg -1 for the predator species and 1000 μg kg -1 for the predator species)

Comparative study of nutritional constituents and the mercury total constituents in fishes commercialized at the city of Cananeia, at the coastal of Sao Paulo, Brazil; Estudo comparativo de constituintes nutricionais e do teor de mercurio total em peixes comercializados na cidade de Cananeia, litoral de Sao Paulo, Brasil

Energy Technology Data Exchange (ETDEWEB)

Nascimento, Soraia M.; Farias, Luciana A.; Curcho, Michel R.M.; Favaro, Deborah I.T., E-mail: soraiamn@hotmail.co [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Braga, Elisabete S., E-mail: edsbraga@usp.b [Universidade de Sao Paulo (LABNUT/USP), SP (Brazil). Inst. Oceanografico. Lab. de Nutrientes, Macronutrientes e Tracos no Oceano

2009-07-01

Aiming the determination of the Hg concentration and the As, Cr and Zn trace elements, four commercial available and frequently consumable fishes by the Cananeia, Sao Paulo, Brazil, were analysed. A total of 53 samples were evaluated as follows: jew fish (Micropogonias furnieri), hake (Macrodon ancylodon), perch (Centropomus undecimalis), and grey mullet (Mugil platanus), all acquired at local fishmonger. The atomic absorption and neutron activation analysis techniques were used for the determination of Hg total levels and trace elements respectively. The trace elements presented large concentration variation among the same specie and the species performed as well. The jew fish presented levels superior to 1000 {mu}g kg{sup -1} for the most individuals analysed and the perch presented chromium levels exceeding the limit of 0.10 mg kg{sup -1} for some individuals. The level of Zn presented values below 50 mg kg{sup -1} established by the Brazilian legislation for all species. The Zn total contents among all species presented values bellow the limits of the Brazilian legislation (500 {mu}g kg{sup -1} for the predator species and 1000 {mu}g kg{sup -1} for the predator species)

Flipped Classroom as an Alternative Strategy for Teaching Stoichiometry

Directory of Open Access Journals (Sweden)

Norrie E. Gayeta

2017-11-01

Full Text Available This study aimed to compare the effectiveness of flipped classroom and traditional classroom instruction in measuring conceptual change and to determine if flipped classroom instruction would be an alternative method of teaching to traditional lecture method. This study covered the level of conceptual understanding of students on stoichiometry and the type of conceptual change before and after exposure to flipped and traditional classroom environment. Qualitative and quantitative research methods were used in the study. Respondents were two sections of third year Bachelor of Secondary Education, Biological Science. Frequency, percentage, ranking, mean, standard deviation, Hake factor test, and t-test were the statistical tools applied to answer specific questions. Results showed profound increase towards conceptual change representing a shift from intuitive understanding to correct incomplete understanding level. Thus, change for the better, in theoretical type was determined from pretest to posttest of students exposed to flipped and traditional classroom. Results also indicated that there is no significant difference on students’ conceptual change on stoichiometry exposed to flipped and traditional classroom environment thus, flipped classroom instruction can be used as an alternative teaching method to traditional lecture method in teaching stoichiometry

Measuring Conceptual Change on Stoichiometry Using Mental Models and IllStructured Problems In a Flipped Classroom Environment

Directory of Open Access Journals (Sweden)

Norrie E. Gayeta

2017-05-01

Full Text Available This study aimed to measure conceptual change on stoichiometry using mental models and ill-structured problems in flipped classroom environment. This study examined the level of conceptual understanding of students on stoichiometry before and after exposure to flipped and traditional lecture method. It also covered the type of conceptual change, and students’ description in flipped classroom environment. Qualitative and quantitative research methods were used in the study. Respondents were two sections of third year Bachelor of Secondary Education, Biological Science. Frequency, percentage, ranking, mean, standard deviation, Hake factor test, and t-test were the statistical tools applied to answer specific questions. Results showed profound increase towards conceptual change representing a shift from intuitive understanding to correct incomplete understanding level. Thus, change for the better, in theoretical type was determined from pretest to posttest of students exposed to flipped and traditional instruction. Results also indicated that there is no significant difference on students’ conceptual change on stoichiometry exposed to flipped and traditional lecture method. Furthermore, students strongly agreed that flipped classroom instruction helped them develop positive attitude towards chemistry and appropriate for learning college chemistry.

Meta-analysis of teaching methods: a 50k+ student study

Science.gov (United States)

Sayre, Eleanor; Archibeque, Benjamin; Gomez, K. Alison; Heckendorf, Tyrel; Madsen, Adrian M.; McKagan, Sarah B.; Schenk, Edward W.; Shepard, Chase; Sorell, Lane; von Korff, Joshua

2015-04-01

The Force Concept Inventory (FCI) and the Force and Motion Conceptual Evaluation (FMCE) are the two most widely-used conceptual tests in introductory mechanics. Because they are so popular, they provide an excellent avenue to compare different teaching methods at different kinds of institutions with varying student populations. We conducted a secondary analysis of all peer-reviewed papers which publish data from US and Canadian colleges and universities. Our data include over fifty thousand students drawn from approximately 100 papers; papers were drawn from Scopus, ERIC, ComPADRE, and journal websites. We augment published data about teaching methods with institutional data such as Carnegie Classification and average SAT scores. We statistically determine the effectiveness of different teaching methods as measured by FCI and FMCE gains and mediated by institutional and course factors. As in the landmark 1998 Hake study, we find that classes using interactive engagement (IE) have significantly larger learning gains than classes using traditional instruction. However, we find a broader distribution of normalized gains occurs in each of traditional and IE classes, and the differences between IE and traditional instruction have changed over time and are more context dependent.

Observer Logistics (OBSLOG) - West Coast Groundfish Observer Program and At-Sea Hake Observer Program data collection, analysis and reporting

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Observer programs are the most comprehensive fishery dependent data collection system for total mortality estimation, protected species monitoring and discard data...

Observer Production (OBSPROD) - West Coast Groundfish Observer Program and At-Sea Hake Observer Program data collection, analysis and reporting

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Observer programs are the most comprehensive fishery dependent data collection system for total mortality estimation, protected species monitoring and discard data...

Evolution in the block: common elements of 5S rDNA organization and evolutionary patterns in distant fish genera.

Science.gov (United States)

Campo, Daniel; García-Vázquez, Eva

2012-01-01

The 5S rDNA is organized in the genome as tandemly repeated copies of a structural unit composed of a coding sequence plus a nontranscribed spacer (NTS). The coding region is highly conserved in the evolution, whereas the NTS vary in both length and sequence. It has been proposed that 5S rRNA genes are members of a gene family that have arisen through concerted evolution. In this study, we describe the molecular organization and evolution of the 5S rDNA in the genera Lepidorhombus and Scophthalmus (Scophthalmidae) and compared it with already known 5S rDNA of the very different genera Merluccius (Merluccidae) and Salmo (Salmoninae), to identify common structural elements or patterns for understanding 5S rDNA evolution in fish. High intra- and interspecific diversity within the 5S rDNA family in all the genera can be explained by a combination of duplications, deletions, and transposition events. Sequence blocks with high similarity in all the 5S rDNA members across species were identified for the four studied genera, with evidences of intense gene conversion within noncoding regions. We propose a model to explain the evolution of the 5S rDNA, in which the evolutionary units are blocks of nucleotides rather than the entire sequences or single nucleotides. This model implies a "two-speed" evolution: slow within blocks (homogenized by recombination) and fast within the gene family (diversified by duplications and deletions).

Foraging Habitat and Chick Diets of Roseate Tern, Sterna dougallii, Breeding on Country Island, Nova Scotia

Directory of Open Access Journals (Sweden)

Jennifer C. Rock

2007-06-01

Full Text Available Breeding seabirds are threatened by human activities that affect nesting and foraging habitat. In Canada, one of the seabirds most at risk of extirpation is the Roseate Tern, Sterna dougallii. Although critical nesting habitat has been identified for the Roseate Tern in Canada, its foraging locations and the diet of its chicks are unknown. Therefore, our goal was to determine the foraging locations and diet of chicks of Roseate Tern breeding on Country Island, Nova Scotia, which is one of Canada's two main breeding colonies. In 2003 and 2004, we radio-tracked the Roseate Tern by plane to locate foraging areas and conducted feeding watches to determine the diet of chicks. Roseate Tern foraged approximately 7 km from the breeding colony over shallow water < 5 m deep. In both years, sand lance, Ammodytes spp., was the most common prey item delivered to chicks, followed by hake, Urophycis spp. Our results are consistent with previous work at colonies in the northeastern United States, suggesting that throughout its range, this species may be restricted in both habitat use and prey selection. The reliance on a specific habitat type and narrow range of prey species makes the Roseate Tern generally susceptible to habitat perturbations and reductions in the availability of prey.

Evaluating machine-learning techniques for recruitment forecasting of seven North East Atlantic fish species

KAUST Repository

Fernandes, José Antonio

2015-01-01

The effect of different factors (spawning biomass, environmental conditions) on recruitment is a subject of great importance in the management of fisheries, recovery plans and scenario exploration. In this study, recently proposed supervised classification techniques, tested by the machine-learning community, are applied to forecast the recruitment of seven fish species of North East Atlantic (anchovy, sardine, mackerel, horse mackerel, hake, blue whiting and albacore), using spawning, environmental and climatic data. In addition, the use of the probabilistic flexible naive Bayes classifier (FNBC) is proposed as modelling approach in order to reduce uncertainty for fisheries management purposes. Those improvements aim is to improve probability estimations of each possible outcome (low, medium and high recruitment) based in kernel density estimation, which is crucial for informed management decision making with high uncertainty. Finally, a comparison between goodness-of-fit and generalization power is provided, in order to assess the reliability of the final forecasting models. It is found that in most cases the proposed methodology provides useful information for management whereas the case of horse mackerel is an example of the limitations of the approach. The proposed improvements allow for a better probabilistic estimation of the different scenarios, i.e. to reduce the uncertainty in the provided forecasts.

Ecological knowledge and incidental capture of sea turtles in São João de Pirabas, Pará, Brazil

Directory of Open Access Journals (Sweden)

Tiago Pereira Brito

2015-09-01

Full Text Available This study aimed to register the ecological knowledge of fishermen from the municipality of São João de Pirabas, Pará, Brazil, regarding the occurrence of sea turtles on the Pará state coast, as well as measure their incidental capture when fishing; to do this, 50 semi-structured interviews were conducted with local fishermen. Fishing was practiced mostly by adult men, who used 7 fishing arts (gillnetting, hook and line, longline, fish corrals, net of tide canals, casting net, and basket trap, mainly aimed at catching king mackerel (Scomberomorus cavalla, serra Spanish mackerel (S. brasiliensis, king weakfish (Macrodon ancylodon, weakfish (Cynoscion spp., hake (Cynoscion spp., catfish (Bagre bagre, and mullet (Mugil spp.. Fishermen observed in the region 5 turtle species, with a more frequent occurrence of Chelonia mydas (100%, Dermochelys coriacea (66%, and Eretmochelys imbricata (46%; the less frequent species are Caretta caretta (16% and Lepidochelys olivacea (8%. The spawning areas of the 3 most common species demonstrate the significance of the Pará state coast for their conservation. Incidental capture was reported by 76% of fishermen, mainly occurring in net, longlines, and fish corrals. Usually, captured animals were released, although there is consumption of sea turtle meat and eggs by fishermen.

Supervised pre-processing approaches in multiple class variables classification for fish recruitment forecasting

KAUST Repository

Fernandes, José Antonio

2013-02-01

A multi-species approach to fisheries management requires taking into account the interactions between species in order to improve recruitment forecasting of the fish species. Recent advances in Bayesian networks direct the learning of models with several interrelated variables to be forecasted simultaneously. These models are known as multi-dimensional Bayesian network classifiers (MDBNs). Pre-processing steps are critical for the posterior learning of the model in these kinds of domains. Therefore, in the present study, a set of \\'state-of-the-art\\' uni-dimensional pre-processing methods, within the categories of missing data imputation, feature discretization and feature subset selection, are adapted to be used with MDBNs. A framework that includes the proposed multi-dimensional supervised pre-processing methods, coupled with a MDBN classifier, is tested with synthetic datasets and the real domain of fish recruitment forecasting. The correctly forecasting of three fish species (anchovy, sardine and hake) simultaneously is doubled (from 17.3% to 29.5%) using the multi-dimensional approach in comparison to mono-species models. The probability assessments also show high improvement reducing the average error (estimated by means of Brier score) from 0.35 to 0.27. Finally, these differences are superior to the forecasting of species by pairs. © 2012 Elsevier Ltd.

Characterizing the complexity of the fleet dynamics for an effective fisheries management: The case of the Cíes Islands (NW Spain

Directory of Open Access Journals (Sweden)

Rosana Ouréns

2015-12-01

Full Text Available We analysed the fishing fleet dynamics in the Cíes Islands, located in a National Land-Marine Park of Galicia. By interviewing fishers we identified the fleet fishing in the study area and obtained temporal data on effort and catch. Then we performed multivariate analyses of the catch profiles to identify the fishing strategies and their temporal dynamics. Our results highlight the complexity of the fishery system, composed of 565 boats that used 19 fishing gears and 33 strategies in an area of 26.6 km2. Octopus and velvet crab pots, gillnets targeting hake, trammel nets targeting European spider crab or ballan wrasse, clam rakes, and hand harvesting of gooseneck barnacles and razor shells are the strategies most used. In addition, most of the boats are generalists and use up to seven different fishing strategies throughout the year. This flexibility of the fleet to change the target species generates a wide diversity of annual fishing patterns that increases the complexity of the fisheries and the difficulty of managing them. The implementation of data collection programmes that include fleet dynamics and spatial data are key factors for developing effective management regulations consistent with the complexity of the system.

Viability and Management Targets of Mediterranean Demersal Fisheries: The Case of the Aegean Sea.

Directory of Open Access Journals (Sweden)

George Tserpes

Full Text Available Management of the Mediterranean demersal stocks has proven challenging mainly due to the multi-species character of the fisheries. In the present work, we focus on the multi-species demersal fisheries of the Aegean Sea (eastern Mediterranean aiming to study the effects of different management measures on the main commercial stocks, as well as to explore the economic viability of the fisheries depending upon these resources, by means of simulated projections. Utilizing the limited available data, our results demonstrated that, under the current exploitation pattern, the economic viability of the fleets is threatened, particularly if fuel prices increase. Additionally, the biological targets set for the most exploited species, such as hake, will not be met under the current management regime. The projections also showed that the only management scenario under which both resource sustainability and economic viability of the fisheries are ensured is the decrease of fleet capacity in terms of vessel numbers. In this case, however, measures to support the fisheries-dependent communities need to be implemented to prevent the collapse of local economies due to employment decrease. Scenarios assuming selectivity improvements would be also beneficial for the stocks but they showed low economic performance and their application would threaten the viability of the fleets, particularly that of the trawlers.

Determination of specific activity of americium and plutonium in selected environmental samples

International Nuclear Information System (INIS)

Trebunova, T.

1999-01-01

The aim of this work was development of method for determination of americium and plutonium in environmental samples. Developed method was evaluated on soil samples and after they was applied on selected samples of fishes (smoked mackerel, herring and fillet from Alaska hake). The method for separation of americium is based on liquid separation with Aliquate-336, precipitation with oxalic acid and using of chromatographic material TRU-Spec TM .The intervals of radiochemical yields were from 13.0% to 80.9% for plutonium-236 and from 10.5% to 100% for americium-241. Determined specific activities of plutonium-239,240 were from (2.3 ± 1.4) mBq/kg to (82 ± 29) mBq/kg, the specific activities of plutonium-238 were from (14.2 ± 3.7) mBq/kg to (708 ± 86) mBq/kg. The specific activities of americium-241 were from (1.4 ± 0.9) mBq/kg to (3360 ± 210) mBq/kg. The fishes from Baltic Sea as well as from North Sea show highest specific activities then fresh-water fishes from Slovakia. Therefore the monitoring of alpha radionuclides in foods imported from territories with nuclear testing is recommended

Cestodes of the blue shark, Prionace glauca (Linnaeus 1758), (Carcharhiniformes: Carcharhinidae), off the west coast of Baja California Sur, Mexico.

Science.gov (United States)

Méndez, Oscar; Galván-Magaña, Felipe

2016-03-03

The cestode species recovered from the spiral intestines of 27 blue sharks (Prionace glauca) (Linnaeus, 1758) are reported from the western coast of Baja California Sur (BCS). The sampling was undertaken on a monthly basis from January 2003 to January 2004. The helminthological examination indicated the presence of four species of cestodes: Platybothrium auriculatum Yamaguti, 1952; Prosobothrium japonicum Yamaguti, 1934; Anthobothrium caseyi (Yamaguti, 1934) Ruhnke & Caira, 2009; and Paraorygmatobothrium prionacis (Yamaguti, 1934) Ruhnke, 1994. Of all the 27 sharks examined, 88.8% were infected with at least one cestode species. The most frequent species was P. auriculatum infecting 85% of the spiral intestines examined. In contrast the species with the highest mean intensity was P. prionacis (80.4 200). The species richness of cestodes in P. glauca is very similar in other regions of the world despite its wide distribution; however, this richness is low compared with other species of sharks within the same family. The feeding and host-specific are important factors that influence the parameters of infection of cestodes in this shark. On the west coast of BCS, Prionace glauca feeds mainly on red crab Pleuroncodes planipes Stimpson, 1860; squids Gonatus californiensis Young, 1972, Ancistrocheirus lesueurii (D'Orbigny, 1842), Haliphron atlanticus Steenstrup, 1861, and low proportion of fish teleosts as Merluccius productus (Ayres, 1855), Sardinops sp. Hubbs, 1929 and Scomber japonicus Houttuyn, 1872. We speculate that these prey could be involved as the second intermediate hosts of these cestodes, as in other members of these genera, although the life cycles of none are known.

Including cetaceans in multi-species assessment models using strandings data: why, how and what can we do about it?

Directory of Open Access Journals (Sweden)

Camilo Saavedra

2014-07-01

questions. Most multispecies models include interactions between commercially exploited species, since those data are more readily available. However, information is needed on at least both the main preys and predators of a selected stock. In the case of European Hake, the species we have focus our research on, cetaceans are their main predator, particularly common and bottlenose dolphins, which have been estimated to remove annually in the Atlantic shelf waters of the Iberian Peninsula, an amount similar to that caught by Spanish and Portuguese fleets (Santos et al., 2013. The European hake is one of the main fishing species of the Spanish and Portuguese fleets operating in the area, and one where more research activity has been concentrated, hence there is plenty of available biological information on growth, reproduction and trophic interactions. As a result, a population model has been built which uses trophic interactions to investigate the relationships between hake and other species. The European hake population is currently divided into two stocks, north and south. The southern hake stock, distributed along the Atlantic coast of the Iberian Peninsula, is annually assessed by the International Council for the Exploration of the Sea (ICES and the Spanish Institute of Oceanography (IEO. For the assessment of this stock, “Gadget” a multi-specific modeling framework is used. Gadget allows the building of minimum realistic models that integrating the main trophic relationships among selected species considered to reflect the main processes in the system. Modeling cetacean populations can allow us to include complex trophic relationships in multispecies models. Furthermore, it will also be a tool to help cetaceans conservation by guiding possible management measures that ensure their viability or recovery. All cetacean species are protected by national and international legislation (e.g. Habitats Directive. However, modeling cetaceans dynamics has a number of problems

Implementation of an active instructional design for teaching the concepts of current, voltage and resistance

Science.gov (United States)

Orlaineta-Agüero, S.; Del Sol-Fernández, S.; Sánchez-Guzmán, D.; García-Salcedo, R.

2017-01-01

In the present work we show the implementation of a learning sequence based on an active learning methodology for teaching Physics, this proposal tends to promote a better learning in high school students with the use of a comic book and it combines the use of different low-cost experimental activities for teaching the electrical concepts of Current, Resistance and Voltage. We consider that this kind of strategy can be easily extrapolated to higher-education levels like Engineering-college/university level and other disciplines of Science. To evaluate this proposal, we used some conceptual questions from the Electric Circuits Concept Evaluation survey developed by Sokoloff and the results from this survey was analysed with the Normalized Conceptual Gain proposed by Hake and the Concentration Factor that was proposed by Bao and Redish, to identify the effectiveness of the methodology and the models that the students presented after and before the instruction, respectively. We found that this methodology was more effective than only the implementation of traditional lectures, we consider that these results cannot be generalized but gave us the opportunity to view many important approaches in Physics Education; finally, we will continue to apply the same experiment with more students, in the same and upper levels of education, to confirm and validate the effectiveness of this methodology proposal.

Rapid determination of strontium-90 in environmental samples by single Cerenkov counting using two different colour quench curves

Energy Technology Data Exchange (ETDEWEB)

Torres, J.M.; Garcia, J.F.; Llaurado, M.; Rauret, G. [Barcelona Univ. (Spain). Dept. de Quimica Analitica

1996-11-01

The validation of the Cerenkov radiation measurement of {sup 90}Y to determine the activity concentration of {sup 90}Sr in environmental samples is described. Liquid-liquid extraction with di-2-ethyhexylphosphoric acid in toluene was used to separate {sup 90}Y from {sup 90}Sr. Optimum conditions for Cerenkov counting (low-level counting option, counting windows, mass of solution to be measured) were established. The need for a counting efficiency correction by using a colour quench curve is stated to be essential, otherwise a significant error may occur. Two different colour quench curves (counting efficiency versus the channel ratio or spectral index parameter) were used and the results were compared. The method was applied to 12 environmental matrices: sea-water, algae, carobs, milk, almonds, hake, honey, shellfish, lamb meat, sardine, pork meat and shore sand. No significant differences were observed on using either of the two colour quench curves for any of these environmental matrices. In order to validate the proposed method, a certified soil reference material (CRM IAEA-375) was used, together with participation in an interlaboratory exercise to determine {sup 90}Sr in a natural water sample. Again, efficiency correction was performed by using either of the two colour quench curves and in both instances the calculated {sup 90}Sr activity concentration was in good agreement with the known values. (Author).

Using video games for volcanic hazard education and communication: an assessment of the method and preliminary results

Science.gov (United States)

Mani, Lara; Cole, Paul D.; Stewart, Iain

2016-07-01

This paper presents the findings from a study aimed at understanding whether video games (or serious games) can be effective in enhancing volcanic hazard education and communication. Using the eastern Caribbean island of St. Vincent, we have developed a video game - St. Vincent's Volcano - for use in existing volcano education and outreach sessions. Its twin aims are to improve residents' knowledge of potential future eruptive hazards (ash fall, pyroclastic flows and lahars) and to integrate traditional methods of education in a more interactive manner. Here, we discuss the process of game development including concept design through to the final implementation on St. Vincent. Preliminary results obtained from the final implementation (through pre- and post-test knowledge quizzes) for both student and adult participants provide indications that a video game of this style may be effective in improving a learner's knowledge. Both groups of participants demonstrated a post-test increase in their knowledge quiz score of 9.3 % for adults and 8.3 % for students and, when plotted as learning gains (Hake, 1998), show similar overall improvements (0.11 for adults and 0.09 for students). These preliminary findings may provide a sound foundation for the increased integration of emerging technologies within traditional education sessions. This paper also shares some of the challenges and lessons learnt throughout the development and testing processes and provides recommendations for researchers looking to pursue a similar study.

Trophic structure in the Gulf of Lions marine ecosystem (north-western Mediterranean Sea) and fishing impacts

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Bănaru, D.; Mellon-Duval, C.; Roos, D.; Bigot, J.-L.; Souplet, A.; Jadaud, A.; Beaubrun, P.; Fromentin, J.-M.

2013-02-01

The Gulf of Lions ecosystem was described using the Ecopath mass-balance model to characterise its structure and functioning and to examine the effects of the multispecific fisheries operating in this area. The model is composed of 40 compartments, including 1 group of seabirds, 2 groups of cetaceans, 18 groups of fish, 12 groups of invertebrates, 5 groups of primary producers, detritus and discards. Input data were based on several recurrent scientific surveys, two alternative datasets for fishing data, stock assessment outputs, stomach content analyses and published information. Results showed that the functional groups were organised into five trophic levels with the highest one represented by dolphins, anglerfish, Atlantic bluefin tuna, European hake and European conger. European pilchard and European anchovy dominated in terms of fish biomass and catch. Other fish with high biomass such as Atlantic mackerel and blue whiting were highly important in the food web. Seabirds, dolphins and cuttlefish-squids represented keystone species. Important coupled pelagic-demersal-benthic interactions were described. The 7 different fisheries analysed were operating at mean trophic levels situated between 2.6 for small artisanal boats, and 4.1 for purse seines (> 24 m) targeting large pelagic fish, indicating an intensively exploited ecosystem. Large trawlers (24-40 m) had the highest impact on most of the groups considered; while purse seines (12-24 m) targeting small pelagic fish had the lowest impact. Preliminary results highlighted the importance of data sources for further ecosystem and fisheries analyses and management scenarios.

Probabilistic risk analysis of mercury intake via food consumption in Spain.

Science.gov (United States)

Moreno-Ortega, Alicia; Moreno-Rojas, Rafael; Martínez-Álvarez, Jesús Román; González Estecha, Montserrat; Castro González, Numa Pompilio; Amaro López, Manuel Ángel

2017-09-01

In Spain, recently, the public institutions have given information to the population in relation to fish consumption and the risk that it poses to health from the ingestion of mercury supposedly contained in the fish. At the same time, several scientific societies have published various works in this direction. All this without there being, up to now, any study on the evaluation of a probabilistic risk from mercury due to fish and seafood intake in Spain, which is the objective of this present work. For that purpose, we took individual data from a survey of the total diet of 3000 people, whose consumption of the principal fish and seafood species (49) was estimated. We compiled individualized data (2000) on the total mercury content of those species, which were completed and validated with bibliographic statistical data. After estimating the distributions of each fish and seafood species, both of their consumption and their mercury content, a simulation was made of the distribution of mercury ingestion from fish and seafood offered by 2.6% of the Spanish population at risk of exceeding total mercury recommendations, and between 12.2% and 21.2% of those exceeding methylmercury ones. The main species responsible were tuna fish, swordfish and hake, and significant differences were identified in fish consumption between sexes and ages, although, in the risk percentage, what stands out is an increase in the latter with an increase in age. Copyright © 2017 Elsevier GmbH. All rights reserved.

Comparison of solid phase extraction, saponification and gel permeation chromatography for the clean-up of microwave-assisted biological extracts in the analysis of polycyclic aromatic hydrocarbons.

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Navarro, P; Cortazar, E; Bartolomé, L; Deusto, M; Raposo, J C; Zuloaga, O; Arana, G; Etxebarria, N

2006-09-22

The feasibility of different clean-up procedures was studied for the determination of polycyclic aromatic hydrocarbons (PAHs) in biota samples such as oysters, mussels and fish liver. In this sense, once the samples were extracted--essentially with acetone and in a microwave system--and before they could be analysed by gas chromatography-mass spectrometry (GC-MS), three different approaches were studied for the clean-up step: solid phase extraction (SPE), microwave-assisted saponification (MAS) and gel permeation chromatography (GPC). The main aim of this work was to maximise the recoveries of PAHs and to minimise the presence of interfering compounds in the last extract. In the case of SPE, Florisil cartridges of 1, 2 and 5 g, and silica cartridges of 5 g were studied. In that case, and with oysters and mussels, microwave-assisted extraction and 5 g Florisil cartridges provided good results. In addition, the concentrations obtained for Standard Reference Material (SRM) NIST 2977 (mussel tissue) were in good agreement with the certified values. In the case of microwave-assisted saponification, the extracts were not as clean as those obtained with 5 g Florisil and this fact lead to overestimate the concentration of the heaviest PAHs. Finally, the cleanest extracts were obtained by GPC. The method was successfully applied to mussels, oysters and hake liver, and the results obtained for NIST 2977 (mussel tissue) were within the confidence interval of the certified reference material for most of the certified analytes.

2013 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake and Pacific Sardine (SaKe 2013) (SH1305, EK60)

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National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC), the Fishery Resources...

2013 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake and Pacific Sardine (SaKe 2015) (SH1507, ME70)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The 2015 SaKe survey will span the west coasts of the U.S. and Canada from approximately lat 32.8?N (San Diego) to approximately lat 54.65?N (Dixon Entrance,...

2013 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake and Pacific Sardine (SaKe 2015) (SH1507, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The 2015 SaKe survey will span the west coasts of the U.S. and Canada from approximately lat 32.8?N (San Diego) to approximately lat 54.65?N (Dixon Entrance,...

Análisis histórico del crecimiento somático de merluza común (Merluccius gayi gayi frente a la costa central de Chile

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Francisco Cerna

2013-07-01

Full Text Available Se estudió el crecimiento somático del stock de merluza común frente a la costa central de Chile, mediante la aplicación de la ecuación de Von Bertalanffy (vB con un modelo No-lineal de Efecto Mixto, sobre los datos edad-talla actual proveniente de la lectura de otolitos realizada por el Instituto de Fomento Pesquero desde 1972. Se estimó la tasa de crecimiento promedio para cada año, desde 1972 a 2009 y se analizaron los parámetros y curvas de crecimiento de vB, agrupados en tres periodos, seleccionados en referencia a importantes variaciones en la biomasa del stock, a saber: 1972-1990, 1991-2003 y 2004-2009. Los resultados indicaron que la tasa de crecimiento promedio mostró variaciones interanuales que no superan ± 1,5 cm LT en torno al promedio histórico de machos y hembras, no mostrando una tendencia persistente hacia el aumento o disminución sostenida. Las curvas de crecimiento obtenidas con los parámetros (vB estimados para los tres periodos indicados, mostraron tanto en hembras como en machos, trayectorias similares hasta los 7 y 8 años de edad, respectivamente. Variaciones posteriores a estas edades se podrían deber a la disminución de los peces de mayor tamaño en la distribución, removidos por el efecto selectivo de la pesca que efectivamente ocasiona variaciones en las curvas ajustadas, pero estas variaciones no son el reflejo de cambios en el crecimiento somático de esas edades en la población. Los resultados permiten concluir que el crecimiento somático de merluza común no ha variado en forma importante desde 1972, los cambios que se observan en peces de mayor edad es probable que obedezcan a causas distintas a la denso-dependencia.

Effects of various cooking processes on the concentrations of arsenic, cadmium, mercury, and lead in foods.

Science.gov (United States)

Perelló, Gemma; Martí-Cid, Roser; Llobet, Juan M; Domingo, José L

2008-12-10

The effects of cooking processes commonly used by the population of Catalonia (Spain) on total arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) concentrations in various foodstuffs were investigated. All food samples were randomly acquired in local markets, big supermarkets, and grocery stores of Reus (Catalonia). Foods included fish (sardine, hake, and tuna), meat (veal steak, loin of pork, breast and thigh of chicken, and steak and rib of lamb), string bean, potato, rice, and olive oil. For each food item, two composite samples were prepared for metal analyses, whose levels in raw and cooked (fried, grilled, roasted, and boiled) samples were determined by inductively coupled plasma-mass spectrometry (ICP-MS). The highest concentrations of As, Hg, and Pb (raw and cooked samples) were mainly found in fish, with a clear tendency, in general, to increase metal concentrations after cooking. However, in these samples, Cd levels were very close to their detection limit. In turn, the concentrations of metals in raw and cooked meat samples were detected in all samples (As) or only in a very few samples (Cd, Hg, and Pb). A similar finding corresponded to string beans, rice, and olive oil, while in potatoes, Hg could not be detected and Pb only was detected in the raw samples. In summary, the results of the present study show that, in general terms, the cooking process is only of a very limited value as a means of reducing metal concentrations. This hypothetical reduction depends upon cooking conditions (time, temperature, and medium of cooking).

Characterisation and standardisation of a red shrimp Aristeus antennatus, (Risso, 1816 fishery off the Alicante gulf (SE Spain

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Mariano García Rodríguez

2003-03-01

Full Text Available The red shrimp (Aristeus antennatus is a target species of a deep trawl fishery in the Gulf of Alicante. This paper describes the fishery by following the activity of this trawl fleet between 1992 and 1999. Principal Components Analysis (PCA of specific catch compositions identified five main components that explained 92% of the variability, and the catches were grouped into three main species: red shrimp, hake and blue whiting. Hierarchical Clustering Grouping of the percentage species catch composition allowed the fleet to be considered as two main groups, according to monthly landings and by differentiating the origin of the catches (slope or shelf. The species composition of the catch and the red shrimp catch rates (CPUE differed between the two fleet groups. The application of Generalised Linear Modelling (GLM to the CPUE series gave consistent indices of abundance. The fleet group, year and season had significant effects on shrimp catch rates, with the fleet group being the most important, and these models explained up to 62% of the total deviance. The abundance indices showed little variation from 1992, although 1994 had the highest value and 1997-1998 the lowest. Comparison with survey indices showed similar trends, while mean uncorrected CPUE differed. Monthly variations of shrimp indices showed a lower abundance in summer, which was attributed to the reproductive patterns of the species. As a result, the use of some fleet grouping techniques is recommended before standardising CPUEs to obtain trends or to calibrate assessment in a fishery.

Feeding by grey seals in the Gulf of St. Lawrence and around Newfoundland

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M O Hammill

2007-01-01

Full Text Available Diet composition of grey seals in the Gulf of St. Lawrence (Gulf and around the coast of Newfoundland, Canada, was examined using identification of otoliths recovered from digestive tracts. Prey were recovered from 632 animals. Twenty-nine different prey taxa were identified. Grey seals sampled in the northern Gulf of St. Lawrence fed mainly on capelin, mackerel, wolffish and lumpfish during the spring, but consumed more cod, sandlance and winter flounder during late summer. Overall, the southern Gulf diet was more diverse, with sandlance, Atlantic cod, cunner, white hake and Atlantic herring dominating the diet. Capelin and winter flounder were the dominant prey in grey seals sampled from the east coast of Newfoundland, while Atlantic cod, flatfish and capelin were the most important prey from the south coast. Animals consumed prey with an average length of 20.4 cm (Range 4.2-99.2 cm. Capelin were the shortest prey (Mean = 13.9 cm, SE = 0.08, N = 1126, while wolffish were the longest with the largest fish having an estimated length of 99.2 cm (Mean = 59.4, SE = 2.8, N = 63. In the early 1990s most cod fisheries in Atlantic Canada were closed because of the collapse of the stocks. Since then they have shown limited sign of recovery. Diet samples from the west coast of Newfoundland indicate a decline in the contribution of cod to the diet from the pre-collapse to the postcollapse period, while samples from the southern Gulf indicate little change in the contribution of cod.

Fish and fishery products trade in Brazil, 2005 to 2015: A review of available data and trends

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Rafael Simões Coelho Barone

Full Text Available ABSTRACT: Along the last ten years fish and fishery product trade in Brazil has been on a downward trajectory turning a profit of US$ 98.6 million in 2005 into a loss of US$ 1.25 billion by 2014. On the other hand, the country is a leading producer of grains and has the third largest animal feed industry in the world, which has added 5.5 million hectares of freshwater reservoirs and 3.5 million km2 of an exclusive marine economic zone in the same period, a sizable potential for development of the aquaculture industry. This study aims at unveiling strategies for the reduction of the deficit in the Brazilian seafood trade balance, based on critical analysis of the quantitative and qualitative characteristics of imported fishery products. The fish and fishery product trade in Brazil, from 2005 to 2015, was studied considering import and export data mined from the Brazilian Ministry of Development, Industry and Commerce databases through the Aliceweb system, and clustered as follows: processing; product species; origin; conservation; and group. The main imported products were gutted fresh fish, highest price (salmon; salted dried fish, higher price (cod; frozen fish fillets, lowest price (fish and hake. The replacement of fish imports by domestic production is not enough to enable consumers to identify the equivalence between products (technical, qualitative or organoleptic. Developing strategies for the production of fish and fishery products at competitive prices and quantities that meet consumer demand is an immediate need, and the development of the aquaculture industry a rational strategy.

Initial Development and Pilot Study Design of Interactive Lecture Demonstrations for ASTRO 101

Science.gov (United States)

Schwortz, Andria C.; French, D. A; Gutierrez, Joseph V; Sanchez, Richard L; Slater, Timothy F.; Tatge, Coty

2014-06-01

Interactive lecture demonstrations (ILDs) have repeatedly shown to be effective tools for improving student achievement in the context of learning physics. As a first step toward systematic development of interactive lecture demonstrations in ASTRO 101, the introductory astronomy survey course, a systematic review of education research, describing educational computer simulations (ECSs) reveals that initial development requires a targeted study of how ASTRO 101 students respond to ECSs in the non-science majoring undergraduate lecture setting. In this project we have adopted the process by which ILDs were designed, pilot-tested, and successfully implemented in the context of physics teaching (Sokoloff & Thornton, 1997; Sokoloff & Thornton, 2004). We have designed the initial pilot-test set of ASTRO 101 ILD instructional materials relying heavily on ECSs. Both an instructor’s manual and a preliminary classroom-ready student workbook have been developed, and we are implementing a pilot study to explore their effectiveness in communicating scientific content, and the extent to which they might enhance students’ knowledge of and perception about astronomy and science in general. The study design uses a pre-/post-test quasi-experimental study design measuring students’ normalized gain scores, calculated as per Hake (1998) and Prather (2009), using a slightly modified version of S. Slater’s (2011) Test Of Astronomy STandards TOAST combined with other instruments. The results of this initial study will guide the iterative development of ASTRO 101 ILDs that are intended to both be effective at enhancing student achievement and easy for instructors to successfully implement.

Registros de representación semiótica del concepto de función exponencial. Parte I

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María G. Castro Rodríguez

2017-01-01

Full Text Available El concepto de función es un objeto matemático fundamental en el proceso de abstracción, en particular, en la función exponencial, la cual es preponderante para el aprendizaje de varios procesos físicos y sociales. Esta función, es parte de los programas de matemáticas desde elinicio de la instrucción escolar hasta el nivel superior, donde la extensión de los mismos, ha limitadosu tiempo de estudio.Aunado a este problema, el sistema tradicional de enseñanza sólo incluye algunos cambios de representación, que de acuerdo con La teoría de registros de representación semiótica (Duval, 1993 no son suficientes para que el estudiante adquiera un entendimiento significativo de esta función. En este artículo se muestra el efecto de la instrucción recibida mediante el coeficiente ganancia normalizada de Hake (1998 a través de una secuencia didáctica. Esta secuencia se fundamenta en los diversos cambios de registros de representación semiótica del concepto de función. Se muestran los efectos de entendimiento de dos grupos, el experimental y el de control. Los resultados indican que el grupo experimental obtuvo una mayor ganancia, y accedió a niveles de entendimiento de Hitt (1998 más altos en comparación con el grupo de control. Además, se obtuvo una correlación de 0.5 entre estos dos índices.

Estimation of the carbon footprint of the Galician fishing activity (NW Spain)

International Nuclear Information System (INIS)

Iribarren, Diego; Vazquez-Rowe, Ian; Hospido, Almudena; Moreira, Maria Teresa; Feijoo, Gumersindo

2010-01-01

The food production system as a whole is recognized as one of the major contributors to environmental impacts. Accordingly, food production, processing, transport and consumption account for a relevant portion of the greenhouse gas (GHG) emissions associated with any country. In this context, there is an increasing market demand for climate-relevant information regarding the global warming impact of consumer food products throughout the supply chains. This article deals with the assessment of the carbon footprint of seafood products as a key subgroup in the food sector. Galicia (NW Spain) was selected as a case study. The analysis is based on a representative set of species within the Galician fishing sector, including species obtained from coastal fishing (e.g. horse mackerel, Atlantic mackerel, European pilchard and blue whiting), offshore fishing (e.g. European hake, megrim and anglerfish), deep-sea fishing (skipjack and yellowfin tuna), extensive aquaculture (mussels) and intensive aquaculture (turbot). The carbon footprints associated with the production-related activities of each selected species were quantified following a business-to-business approach on the basis of 1 year of fishing activity. These individual carbon footprints were used to calculate the carbon footprint for each of the different Galician fisheries and culture activities. Finally, the lump sum of the carbon footprints for coastal, offshore and deep-sea fishing and extensive and intensive aquaculture brought about the carbon footprint of the Galician fishing activity (i.e., capture and culture). A benchmark for quantifying and communicating emission reductions was then provided, and opportunities to reduce the GHG emissions associated with the Galician fishing activity could be prioritized.

Effect of annatto seed and coriander leaves as natural antioxidants in fish meatballs during frozen storage.

Science.gov (United States)

Sancho, Renata Aparecida Soriano; de Lima, Fabíola Aliaga; Costa, Gabriel Guerra; Mariutti, Lilian Regina Barros; Bragagnolo, Neura

2011-08-01

The effects of annatto (0.1 g/100g) and coriander (0.5 g/100g) were assessed against lipid oxidation in white hake meatballs cooked in boiling water (95 ± 1 °C) for 30 min and stored at -18 °C for 120 d. The fatty acids (FA) and the nutritional quality, cholesterol, cholesterol oxides, thiobarbituric acid reactive substances (TBARS) values, and conjugated dienes were analyzed to follow the course of oxidation. Annatto and coriander were efficient in the control of lipid oxidation, also preserving the essential FA. At 120 d of storage, the eicosapentaenoic acid (EPA) concentration decreased respectively by 43%, 32%, 12%, and 9% in the control, coriander, annatto, and annatto + coriander patties. For docosahexaenoic acid (DHA), these concentrations decreased, respectively, 44%, 30%, 11%, and 7%, revealing a probable synergistic effect among the antioxidant compounds present in both spices. On the other hand, annatto and coriander were not able to act protecting the meatballs against lipid oxidation when they were cooked, also not exerted any effect in the cholesterol oxidation. Spices, especially coriander and annatto, can be an alternative to substitute synthetic additives with antioxidants to prevent loss of important unsaturated fatty acids (UFA) in fish meatballs during frozen storage for 120 d. The maximum effect was observed when 0.5% coriander and 0.1% annatto were used in combination. Cooking did not induce the formation of cholesterol oxides, compounds that can cause more health damages than cholesterol itself; however, during storage the cholesterol oxides levels presented a little increase regardless of spice addition. © 2011 Institute of Food Technologists®

Estimation of the carbon footprint of the Galician fishing activity (NW Spain).

Science.gov (United States)

Iribarren, Diego; Vázquez-Rowe, Ian; Hospido, Almudena; Moreira, María Teresa; Feijoo, Gumersindo

2010-10-15

The food production system as a whole is recognized as one of the major contributors to environmental impacts. Accordingly, food production, processing, transport and consumption account for a relevant portion of the greenhouse gas (GHG) emissions associated with any country. In this context, there is an increasing market demand for climate-relevant information regarding the global warming impact of consumer food products throughout the supply chains. This article deals with the assessment of the carbon footprint of seafood products as a key subgroup in the food sector. Galicia (NW Spain) was selected as a case study. The analysis is based on a representative set of species within the Galician fishing sector, including species obtained from coastal fishing (e.g. horse mackerel, Atlantic mackerel, European pilchard and blue whiting), offshore fishing (e.g. European hake, megrim and anglerfish), deep-sea fishing (skipjack and yellowfin tuna), extensive aquaculture (mussels) and intensive aquaculture (turbot). The carbon footprints associated with the production-related activities of each selected species were quantified following a business-to-business approach on the basis of 1year of fishing activity. These individual carbon footprints were used to calculate the carbon footprint for each of the different Galician fisheries and culture activities. Finally, the lump sum of the carbon footprints for coastal, offshore and deep-sea fishing and extensive and intensive aquaculture brought about the carbon footprint of the Galician fishing activity (i.e., capture and culture). A benchmark for quantifying and communicating emission reductions was then provided, and opportunities to reduce the GHG emissions associated with the Galician fishing activity could be prioritized. Copyright © 2010 Elsevier B.V. All rights reserved.

Genomic and phylogenetic characterization of luminous bacteria symbiotic with the deep-sea fish Chlorophthalmus albatrossis (Aulopiformes: Chlorophthalmidae).

Science.gov (United States)

Dunlap, Paul V; Ast, Jennifer C

2005-02-01

Bacteria forming light-organ symbiosis with deep-sea chlorophthalmid fishes (Aulopiformes: Chlorophthalmidae) are considered to belong to the species Photobacterium phosphoreum. The identification of these bacteria as P. phosphoreum, however, was based exclusively on phenotypic traits, which may not discriminate between phenetically similar but evolutionarily distinct luminous bacteria. Therefore, to test the species identification of chlorophthalmid symbionts, we carried out a genomotypic (repetitive element palindromic PCR genomic profiling) and phylogenetic analysis on strains isolated from the perirectal light organ of Chlorophthalmus albatrossis. Sequence analysis of the 16S rRNA gene of 10 strains from 5 fish specimens placed these bacteria in a cluster related to but phylogenetically distinct from the type strain of P. phosphoreum, ATCC 11040(T), and the type strain of Photobacterium iliopiscarium, ATCC 51760(T). Analysis of gyrB resolved the C. albatrossis strains as a strongly supported clade distinct from P. phosphoreum and P. iliopiscarium. Genomic profiling of 109 strains from the 5 C. albatrossis specimens revealed a high level of similarity among strains but allowed identification of genomotypically different types from each fish. Representatives of each type were then analyzed phylogenetically, using sequence of the luxABFE genes. As with gyrB, analysis of luxABFE resolved the C. albatrossis strains as a robustly supported clade distinct from P. phosphoreum. Furthermore, other strains of luminous bacteria reported as P. phosphoreum, i.e., NCIMB 844, from the skin of Merluccius capensis (Merlucciidae), NZ-11D, from the light organ of Nezumia aequalis (Macrouridae), and pjapo.1.1, from the light organ of Physiculus japonicus (Moridae), grouped phylogenetically by gyrB and luxABFE with the C. albatrossis strains, not with ATCC 11040(T). These results demonstrate that luminous bacteria symbiotic with C. albatrossis, together with certain other strains of

Thinking Like a Scientist: The RITES Path for K-12 Students to Learn the Scientific Method

Science.gov (United States)

Murray, D. P.; Dooley, H., Jr.; Cardace, D.

2015-12-01

Bringing Research on Learning to the Geosciences (Manduca et al, 2002) stated that "An overaching goal for geoscience education is to help every student to 'think like a scientist'", and that continues to challenge geoscience education. The Rhode Island Technology Enhanced Science (RITES) project addresses that goal, and this presentation chronicles that successful effort. RITES strives to improve science education by providing professional development (PD) to the majority of science teachers at the 5th through 12th grade levels throughout Rhode Island. The PD is presented through ~forty 2.5 day workshops that emphasize the innovative use of technology and best teaching practices, consistent with the recommendations detailed in Manduca et al (2002). The presentation will focus on two of these workshops that provide middle and high school teachers with strategies and techniques for guiding student-run explorations of earthquakes as a result of tectonic plate movements. Teachers address these topics much as a scientist would by carrying out the following activities: 1) Identifying the relationships between faults, EQs and plate boundaries; 2) Using GPS data to quantify interseismic deformation; 3) Constructing an Earthquake machine; and 4) Scaling their observations from desktop to crustal scale, and (5) Using the results to forecast earthquakes along the SAF and to estimate the magnitude of earthquakes on ancient faults. As it is unrealistic to expect teachers to be able to incorporate all of this material into their syllabi, we have introduced the concept of Subtle Shifts (Exploratorium, 2006) as a means by which they can easily blend workshop material into their existing courses. Teacher surveys reflect a high level of satisfaction (81-100%), and pre- and post-evaluations show significant normalized gains (Hake, 1998), in about 90% of the courses. Moreover, students of RITES teachers demonstrate statistically significant gains in inquiry skills and content

Analysis of different thermal processing methods of foodstuffs to optimize protein, calcium, and phosphorus content for dialysis patients.

Science.gov (United States)

Vrdoljak, Ivica; Panjkota Krbavčić, Ines; Bituh, Martina; Vrdoljak, Tea; Dujmić, Zoran

2015-05-01

To analyze how different thermal processing methods affect the protein, calcium, and phosphorus content of hospital food served to dialysis patients and to generate recommendations for preparing menus that optimize nutritional content while minimizing the risk of hyperphosphatemia. Standard Official Methods of Analysis (AOAC) methods were used to determine dry matter, protein, calcium, and phosphorus content in potatoes, fresh and frozen carrots, frozen green beans, chicken, beef and pork, frozen hake, pasta, and rice. These levels were determined both before and after boiling in water, steaming, stewing in oil or water, or roasting. Most of the thermal processing methods did not significantly reduce protein content. Boiling increased calcium content in all foodstuffs because of calcium absorption from the hard water. In contrast, stewing in oil containing a small amount of water decreased the calcium content of vegetables by 8% to 35% and of chicken meat by 12% to 40% on a dry weight basis. Some types of thermal processing significantly reduced the phosphorus content of the various foodstuffs, with levels decreasing by 27% to 43% for fresh and frozen vegetables, 10% to 49% for meat, 7% for pasta, and 22.8% for rice on a dry weight basis. On the basis of these results, we modified the thermal processing methods used to prepare a standard hospital menu for dialysis patients. Foodstuffs prepared according to the optimized menu were similar in protein content, higher in calcium, and significantly lower in phosphorus than foodstuffs prepared according to the standard menu. Boiling in water and stewing in oil containing some water significantly reduced phosphorus content without affecting protein content. Soaking meat in cold water for 1 h before thermal processing reduced phosphorus content even more. These results may help optimize the design of menus for dialysis patients. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights

Should Ecosystem Management Involve Active Control of Species Abundances?

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Robert B. Lessard

2005-12-01

Full Text Available We review four case studies in which there is a risk of extinction or severe reduction in highly valued species if we ignore either, or both, of two ecosystem control options. "Symptomatic control" implies direct control of extinction risk through direct harvesting or culling of competitors and predators. "Systemic control" implies treating the causes of the problem that led to an unnaturally high abundance in the first place. We demonstrate, with a discussion of historically observed population trends, how surprising trophic interactions can emerge as a result of alterations to a system. Simulation models were developed for two of the case studies as aids to adaptive policy design, to expose possible abundance changes caused by trophic interactions and to highlight key uncertainties about possible responses to ecosystem management policies involving active intervention to control abundances. With reasonable parameter values, these models predict a wide range of possible responses given available data, but do indicate a good chance that active control would reverse declines and reverse extinction risks. We find that controlling seal (Phoca vitulina populations in the Georgia Strait increases juvenile survival rates of commercial salmon (Oncorhynchus spp. species, but that commensurate increases in hake populations from decreased seal predation could be a compensatory source of predation on juvenile salmon. We also show that wolf (Canis lupus control and moose (Alces alces harvest bring about a recovery in caribou (Rangifer tarandus caribou populations, where simple habitat protection policies fail to recover caribou before wolf predation causes severe declines. The results help address a common problem in disturbed ecosystems, where controlling extinction risks can mean choosing between active control of species abundance or establishing policies of protection, and allowing threatened species to recover naturally.

Implementation literacy strategies on health technology theme Learning to enhance Indonesian Junior High School Student's Physics Literacy

Science.gov (United States)

Feranie, Selly; Efendi, Ridwan; Karim, Saeful; Sasmita, Dedi

2016-08-01

according to Hake's classification.

The economy of chip, tree section and short wood methods in the procurement of a pulp mill; Hake-, puu- ja puutavaralajimenetelmien taloudellisuus massatehtaan kuitu- ja energiapuun hankinnassa

Energy Technology Data Exchange (ETDEWEB)

Imponen, V [Metsaeteho Oy, Helsinki (Finland)

1997-12-01

Regional forest management plans for Finland`s private, non-industrial forestry indicate that first thinnings account for 13 % of the felling potential in these forests. The majority of first thinnings focus on pine-dominated stands. First-thinnings wood represents 29 % of the allowable cut consisting of pine pulpwood. However, small-diameter pine has not enjoyed great demand as raw material by the chemical pulp industry due to the high associated production costs and due to its inferior fibre properties when compared to large-sized softwood logs. Consequently, research and development work has been focused on the procurement, handling and usage of small-diameter wood, and especially of first-thinning pine. Both defibration and use as fuel are options when considering how to exploit small-diameter softwood raw material. Integrated procurement of industrial wood and wood fuel have improved the profitability of wood from thinnings in pulp manufacture and in energy generation at the mill. These methods would appear to be economic in regard to both the wood procurement of the pulp mills even at the present prices paid for alternative fuels. Advances in combustion technology and increased generation of electric power improve the competitiveness of methods based on the harvesting tree sections in comparison with the shortwood system yielding delimbed roundwood. The adoption of longer timber lorry-trailer combination as recognised by EU directives will have the effect of reducing the transportation costs for non-delimbed and partially delimbed wood. (orig.)

Responsible fisheries summary: 2000-2001 annual report

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-05-01

The energy required to harvest fish from the sea is greater than that required for the production of any other primary food product. Increasing energy efficiency in the fishing industry makes sense, especially in light of the recent increases in fossil fuel prices and the increased concern expressed about greenhouse gas emissions. As a result, Fisheries and Oceans Canada collaborated with partners from the fishing industry, and with support provided by Natural Resources Canada, Program of Energy Research and Development (PERD) to initiate several projects aimed at improving the energy efficiency of fishing gear and related components. During the period April 2000 to March 2001, five projects were completed and two more were initiated. The goals were the determination of the effectiveness of new gear prototypes and fishing techniques towards a reduction in energy consumption. Detailed experimental protocols, gear prototypes, flume tank testing, at-sea trials, analysis of results, and reporting to industry and stakeholders are some of the facets common to most of the projects. Potential fuel savings, in the range of 2,330,000 liters annually for the shrimp trawler fleet were identified by testing new composite trawl netting. Potential fuel savings of 850,000 liters in Silver Hake could be realized by using new small diameter high tenacity braided polyethylene twines in trawl netting, when compared to standard polyethylene. A reduction of approximately 13 per cent in fuel consumption per kilogram of fish harvested is possible, as demonstrated by the testing of new Triplex Trawl design, with three codends rather than one. Operational costs and fuel consumption are both reduced through the use of the new Millennium trawl design using small mesh size in forepart and body of trawl, as shown by the Greenland Halibut (Turbot) selectivity experiments. Meshing is reduced, as is the by-catch of small Turbot. Potential benefits of lighter weight materials of construction were

Does Structured Quizzing with Process Specific Feedback Lead to Learning Gains in an Active Learning Geoscience Classroom?

Science.gov (United States)

Palsole, S.; Serpa, L. F.

2013-12-01

There is a great realization that efficient teaching in the geosciences has the potential to have far reaching effects in outreach to decision and policy makers (Herbert, 2006; Manduca & Mogk, 2006). This research in turn informs educators that the geosciences by the virtue of their highly integrative nature play an important role in serving as an entry point into STEM disciplines and helping developing a new cadre of geoscientists, scientists and a general population with an understanding of science. Keeping these goals in mind we set to design introductory geoscience courses for non-majors and majors that move away from the traditional lecture models which don't necessarily contribute well to knowledge building and retention ((Handelsman et al., 2007; Hake, 1997) to a blended active learning classroom where basic concepts and didactic information is acquired online via webquests, lecturettes and virtual field trips and the face to face portions of the class are focused on problem solving exercises. The traditional way to ensure that students are prepared for the in-class activity is to have the students take a quiz online to demonstrate basic competency. In the process of redesign, we decided to leverage the technology to build quizzes that are highly structured and map to a process (formation of divergent boundaries for example) or sets of earth processes that we needed the students to know before in-class activities. The quizzes can be taken multiple times and provide process specific feedback, thus serving as a heuristic to the students to ensure they have acquired the necessary competency. The heuristic quizzes were developed and deployed over a year with the student data driving the redesign process to ensure synchronicity. Preliminary data analysis indicates a positive correlation between higher student scores on in-class application exercises and time spent on the process quizzes. An assessment of learning gains also indicate a higher degree of self

Utilization of agrarian potentials'. Challenges for agriculturists and society; Agrar-Potenziale nutzen.. Herausforderung fuer Landwirte und Gesellschaft

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

Within the scope of the meeting 'Utilization of agrarian potentials' held by Deutsche Landwirtschaftliche Gesellschaft e.V. at 8th to 10th January, 2008, in Muenster (Federal Republic of Germany) the following lectures were held: (a) The world markets move - challenges for production (Joachim von Braun); (b) Global markets - future terms of references for the agriculture: guidelines for future strategies under new objectives (Juergen Zeddies); (c) Structural change and globalization - challenges for cooperative societies as market partners of the agriculture (Andreas Schueren, Dieter Hake); (d) More efficient utilization of scarce resources - we need changed thought patterns and decision patterns (Carl-Albrecht Bartmer); (e) Optimal intensities in the agriculture - the requirement of the hour: Adjustment of production at optimal intensity (Theo Jachmann); (f) Growth potentials of selected locations for the agriculture - area productivity in the international comparison (Klaus Nehring); (g) Optimization of the intensities in the crop farming - new challenges, possible adjustments (Hubertus Paetow); (h) Considering inventory management? The fertilization of tomorrow (Klaus Muenchhoff); (i) Value added chain of grain - quality requirements from the view of the traceability: The test system grain (Petra Melisch); (j) Young farmers full of optimism - current results of interview for the estimation of the situation and future and to efficiency potentials (Marika Prasser-Strith); (k) The responsibility for the soil - challenges at technology for cultivation and tillage (Franz-Georg von Busse); (l) The sustainable use of the plough land is an obligation - plough land is precious. (Lothar Hoevelmann); (m) Development of milk cattle companies till 2015 - strategic future planning now necessarily (Johannes Thomsen); (n) The ethical responsibility for a sustainable and global development - agriculture and nutrition (Beatrice van Saan-Klein, Markus Vogt); (o) Ethical

Apports en DHA (acide gras oméga-3 par les poissons et les fruits de mer consommés en France

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Bourre Jean-Marie

2007-01-01

Full Text Available This present work measures the contributions of seafood (finfish and shellfish, wild and farmed to the intakes of DHA in France, year 2005, and consequently to the French recommended daily intakes (RDA of DHA. For this purpose, we measured the concentrations of DHA in each individual seafood by analysis of many published data. We also determined the exact consumption of the main products of seafood (fishing and farming in France (year 2005 using the modified method of the dietary intake measurement defined by the FAO. For year 2005, the 34 species of finfish and shellfish whose DHA contents are known account for 150% of the RDA of this omega-3 fatty acid. Taking all the species individually and extrapolating to include those whose DHA contents are not known, gives 156% of the RDA. The 10 greatest contributors to the DHA intake in the present diet are: salmon (47.6 mg/day/person, sardine (28.4, tuna (20.5, mackerel (15.7, herring (12.4, Alaskan pollock (8.9, cod (6.9, trout (6.5, hake (4.7, saithe (4.6. The 5 species of oily fish (salmon, sardine, tuna, mackerel and herring provide 63% of the DHA intake, and thus approx 95% of the French RDA. Besides DHA, seafood contains low amounts of ALA, but it can very high in farmed fish fed on rapeseed or linseed products. Omega-3 fatty acids (including EPA and DHA have an important role in human diet, both for prevention and the therapy of different pathologies. Data from many epidemiological studies has shown an inverse association between fish consumption, generally oily fish, and reductions in certain diseases. Although number of people do not lack dietary DHA, others, mainly pregnant women and nursing mothers and those people whose life styles or socio-economic positions restrict their seafood intakes, would benefit greatly from an increased intake of this omega-3 fatty acid.

METALES PESADOS (CD Y PB) Y COMPUESTOS ORGANICLORADOS (PESTICIDAS ORGANOCLORADOS Y BIFENILOS POLICLORADOS) EN PECES DE DIFERENTES NIVELES TROFICOS (ENGRAULIS RINGENS, TRACHURUS MURPHYI Y MERLUCCIUS GAYI), EN LA REGION DEL BIOBIO, CHILE.

OpenAIRE

FUENTEALBA CRUZ, MARTA; FUENTEALBA CRUZ, MARTA

1998-01-01

Las hipótesis que explican la presencia de contaminantes en los tejidos de organismos visos, incluyen la biomagnificación y la hidrot'ohicidad la prinlera, señala que algunos contaminantes pueden aumentar sus niveles a través de las cadenas tróficas, por 91p.

The economy of chip, whole-tree and short-wood methods in the pulpwood and fuelwood procurement of a pulp mill; Hake-, puu- ja puutavaralajimenetelmien taloudellisuus massatehtaan kuitu- ja energiapuun hankinnassa

Energy Technology Data Exchange (ETDEWEB)

Imponen, V [Metsaeteho, Helsinki (Finland)

1997-12-31

Branch-mass models, applicable for different kinds of technical/economical inspections of timber procurement, based on large data collections of the Finnish Forest Research Institute, were developed in the project. These models are based on the assumption that the branch-mass distribution inside the top-end of different tree-species resembles each-other. The production costs of pulp produced from first-thinning pine were lowest when the minimum diameter of the pulpwood varied between 6 - 9 cm, then the relative costs varied between 101 - 99. The production costs consisted of timber procurement costs, variable industrial timber processing and pulping costs, and secondary product reimbursements. In addition to the calculational inspections, the effects of the dimensions of pulpwood and the harvesting technology on profitability of harvesting of first thinning pine, on debarking, on the chip-size distribution and on fiber properties, were studied in the research. The profitability of harvesting is increased by about 10 % when the minimum diameter is decreased from 7 cm to 5 cm. This requires, however, that the size of the minimum-stem is not decreased

The economy of chip, whole-tree and short-wood methods in the pulpwood and fuelwood procurement of a pulp mill; Hake-, puu- ja puutavaralajimenetelmien taloudellisuus massatehtaan kuitu- ja energiapuun hankinnassa

Energy Technology Data Exchange (ETDEWEB)

Imponen, V. [Metsaeteho, Helsinki (Finland)

1996-12-31

Branch-mass models, applicable for different kinds of technical/economical inspections of timber procurement, based on large data collections of the Finnish Forest Research Institute, were developed in the project. These models are based on the assumption that the branch-mass distribution inside the top-end of different tree-species resembles each-other. The production costs of pulp produced from first-thinning pine were lowest when the minimum diameter of the pulpwood varied between 6 - 9 cm, then the relative costs varied between 101 - 99. The production costs consisted of timber procurement costs, variable industrial timber processing and pulping costs, and secondary product reimbursements. In addition to the calculational inspections, the effects of the dimensions of pulpwood and the harvesting technology on profitability of harvesting of first thinning pine, on debarking, on the chip-size distribution and on fiber properties, were studied in the research. The profitability of harvesting is increased by about 10 % when the minimum diameter is decreased from 7 cm to 5 cm. This requires, however, that the size of the minimum-stem is not decreased

Hábitos alimentarios de Dosidicus gigas (D' Orbigny, 1835 (Cephalopoda: Teuthoidea frente a la costa centro-sur de Chile Feeding habits of Dosidicus gigas (D'Orbigny, 1835 (Cephalopoda: Teuthoidea in the central-south coast off Chile

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PATRICIO ULLOA

2006-12-01

Full Text Available Se estudiaron los hábitos alimentarios del calamar rojo Dosidicus gigas (D'Orbigny, 1835 frente a la costa de Chile centro-sur, durante el invierno del año 2005. Se examinaron un total de 52 estómagos, en todos los cuales había contenido alimentario. Los ejemplares provenían de pescas efectuadas por la flota arrastrera industrial que opera entre 36°39' S y 38°55'S sobre la merluza común Merluccius gayi (Guichenot 1848 y a una profundidad media de 290 m sobre la plataforma continental. Para la descripción del espectro trófico, alimento principal y el establecimiento de las eventuales diferencias sexuales u ontogenéticas en la frecuencia de aparición de los ítemes presa, se utilizaron los métodos numérico, gravimétrico, de frecuencia de ocurrencia, índice de importancia relativa (IIR e índice de similitud porcentual (ISP. No se observaron diferencias sexuales ni ontogenéticas en la frecuencia de aparición de los ítemes presa. Los resultados muestran que D. gigas es un depredador oportunista, principalmente ictiófago, y secundariamente malacófago (incluye el canibalismo y carcinófago. Se discuten los eventuales motivos e implicancias de tal conductaA study on the feeding habits of the jumbo squid Dosidicus gigas (D'Orbigny, 1835 was carried out during the winter season 2005, in waters of the Chilean central and southern Pacific. A total of 52 jumbo squid stomachs from the fishing of the continental slope were collected and examined, in the Eighth and Ninth regions, between 36°40' S and 38°55'S, at an average depth of 290 m. To determine the trophic spectrum, the feeding preferences and the importance of the sex and ontogenetic condition in the diet, the numeric, gravimetric, frequency of occurrence methods, and the index of relative importance and dietary similarity were utilized. The frequency of the prey did not vary with relation to the sex and ontogenetic conditions, and was besides a hight trophic similarity in such

Quality loss assessment in fish-based ready-to-eat foods during refrigerated storage

Directory of Open Access Journals (Sweden)

Pourashouri, P.

2013-03-01

Full Text Available The present research addresses the quality loss in two different ready-to-eat (RTE seafoods. With this aim, chemical and microbiological parameters were measured in tuna lasagne (TL and hake roe foods which were refrigerated (4°C for up to 35 and 71 days, respectively. Both foods showed a significant lipid oxidation (peroxide and interaction compound formation development with storage time, which was especially marked in the case of the TL product, which also underwent an important lipid hydrolysis development. Both RTE products showed a low microbial development, no matter how much time had elapsed since the expiration dates; thus, low total viable count scores and volatile amine formation were attained while the presence of pathogen microorganisms was not detected. In view of the current increasing consumer demand for high quality refrigerated foods, the assessment of lipid damage related to nutritional and sensory values is recommended when fish-based RTE products are encountered.

Se estudió la pérdida de calidad de dos productos marinos elaborados (lasaña de atún, TL; huevas de merluza conservados en refrigeración (4 °C durante 35 y 71 días, respectivamente. Ambos alimentos mostraron un desarrollo importante de la oxidación lipídica (formación de peróxidos y compuestos de interacción durante el periodo de conservación, siendo mayor en el caso de TL; asimismo, el producto TL experimentó un importante desarrollo de hidrólisis lipídica. Sin embargo, ambos alimentos experimentaron un desarrollo bajo en microorganismos mesófilos y aminas volátiles; por otra parte, no maniferstaron presencia de microorganismos patógenos a lo largo del periodo de conservación, a pesar de sobrepasar el tiempo de caducidad. De acuerdo con la creciente demanda de nuevas preparaciones de alimentos refrigerados de calidad alta, se recomienda el estudio de las alteraciones lipídicas en elaboraciones basadas en alimentos de origen marino

Improvement of Dielectric, Magnetic and Thermal Properties of OPEFB Fibre–Polycaprolactone Composite by Adding Ni–Zn Ferrite

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Ahmad F. Ahmad

2017-02-01

Full Text Available The dielectric and magnetic behaviour and thermal properties of composites based on nickel–zinc ferrite (NZF filler can be improved by the addition of various types of materials. Amongst others, ferrite–polymer composites have been subjected to a wide range of research, due to their extensive applications: electromagnetic interference shielding, microwave absorption, electrodes and sensors. Currently, the interest in scientific and technical searches for the potential outcomes of ferrite–polymer materials due to their different uses in applications such as telecommunication applications, microwave devices and electromagnetic interference shielding has been growing stronger. The dielectric and magnetic behaviour and thermal properties for such composite materials depend on size, shape and the amount of filler addition. Nickel–zinc ferrite material was prepared using the conventional solid-state reaction technique. This study highlights the development of microwave-absorbing material from NZF by adding natural fibres, Oil Palm Empty Fruit Bunch (OPEFB and polycaprolactone (PCL. OPEFB is considered in this study because it is a solid waste product of the oil palm milling process which is widely and cheaply available. The use of OPEFB in this product may save the environment from oil palm solid waste. A Thermal Hake blending machine was used in blending the powder structure of NZF + OPEFB + PCL, which made it homogeneous. These composites were characterized by the use of Fourier transform infrared (FTIR spectrometry and scanning electron microscopy (SEM. The thermal degradation behaviour of the composites was analyzed using thermogravimetric analysis (TGA and differential thermogravimetric (DTG thermograms. The effective permittivity and effective permeability was obtained over a broad frequency range from 8 to 12 GHz at room temperature. It was observed that the values of effective permittivity and permeability increased as the content of

The Principles of Buoyancy in Marine Fish Eggs and Their Vertical Distributions across the World Oceans.

Science.gov (United States)

Sundby, Svein; Kristiansen, Trond

2015-01-01

recruitment to the population. An example of adaptation to such conditions is Cape hake spawning above the critical layer in the Northern Benguela upwelling ecosystem. The eggs rise slowly in the onshore subsurface current below the Ekman layer, hence being advected inshore where the hatched larvae concentrate with optimal feeding conditions.

An in vitro study of urea, water, ion and CO2/HCO3- transport in the gastrointestinal tract of the dogfish shark (Squalus acanthias): the influence of feeding.

Science.gov (United States)

Liew, Hon Jung; De Boeck, Gudrun; Wood, Chris M

2013-06-01

In vitro gut sac preparations made from the cardiac stomach (stomach 1), pyloric stomach (stomach 2), intestine (spiral valve) and colon were used to examine the impact of feeding on transport processes in the gastrointestinal tract of the dogfish shark. Preparations were made from animals that were euthanized after 1-2 weeks of fasting, or at 24-48 h after voluntary feeding on a 3% ration of teleost fish (hake). Sacs were incubated under initially symmetrical conditions with dogfish saline on both surfaces. In comparison to an earlier in vivo study, the results confirmed that feeding caused increases in H(+) secretion in both stomach sections, but an increase in Cl(-) secretion only in stomach 2. Na(+) absorption, rather than Na(+) secretion, occurred in both stomach sections after feeding. All sections of the tract absorbed water and the intestine strongly absorbed Na(+) and Cl(-), regardless of feeding condition. The results also confirmed that feeding increased water absorption in the intestine (but not in the colon), and had little influence on the handling of Ca(2+) and Mg(2+), which exhibited negligible absorption across the tract. However, K(+) was secreted in the intestine in both fasted and fed preparations. Increased intestinal water absorption occurred despite net osmolyte secretion into the mucosal saline. The largest changes occurred in urea and CO2/HCO3(-) fluxes. In fasted preparations, urea was absorbed at a low rate in all sections except the intestine, where it was secreted. Instead of an increase in intestinal urea secretion predicted from in vivo data, feeding caused a marked switch to net urea absorption. This intestinal urea transport occurred at a rate comparable to urea reabsorption rates reported at gills and kidney, and was apparently active, establishing a large serosal-to-mucosal concentration gradient. Feeding also greatly increased intestinal CO2/HCO3(-) secretion; if interpreted as HCO3(-) transport, the rates were in the upper range

Osmoregulation, ionoregulation and acid-base regulation by the gastrointestinal tract after feeding in the elasmobranch (Squalus acanthias).

Science.gov (United States)

Wood, Chris M; Kajimura, Makiko; Bucking, Carol; Walsh, Patrick J

2007-04-01

In order to study the physiological consequences of voluntary feeding in the gastrointestinal tract of a ureotelic marine elasmobranch, dogfish (fasted for 96 h) were sampled at various times up to 360 h after consuming a 5-6% ration of teleost fish (hake) under natural feeding conditions. Digestion and absorption were completed between 120 and 360 h post-feeding. The tissue masses of different segments of the gastrointestinal tract increased and decreased markedly as the chyme moved through, mainly because of fluid engorgement rather than hyperplasia. In fasted dogfish, the cardiac and pyloric stomachs contained only small volumes of highly acidic fluid (pH 1.77+/-1.12, 2.05+/-0.08) similar in composition to seawater. Feeding resulted in gastric pHs of 3.20+/-0.31 and 3.95+/-0.40 at 6 h, followed by slow declines through 60 h. An alkaline tide in the blood also occurred at 6 h. In the face of large changing masses of highly acidic chyme in the stomachs, the pH (6.50+/-0.10), ionic composition and volume of chyme in the intestine (spiral valve) were precisely regulated from 6 to 60 h post-feeding at very different values from those in the stomachs, and intestinal HCO3(-) remained low (5.12+/-0.83 mmol l(-1)). The colon was usually empty and its pH constant at 7.20+/-0.16 at all times. Despite the ingestion of strongly hypo-osmotic teleost tissue, the osmolality of the chyme remained in equilibrium with that of the blood plasma in all segments at all times after feeding. Much of the osmotic equilibration was because of the secretion of urea into the chyme, particularly in the intestine. After feeding, gastric fluid concentrations of Na(+) and Mg(2+) declined, K(+) and Ca(2+) increased, whereas Cl(-) exhibited little change, indicating that additional drinking of seawater was minimal. Na(+), K(+), water and especially Cl(-) were absorbed in the intestine, whereas Mg(2+) and Ca(2+) were largely excluded. Our results illustrate the complex integration of digestive and

The Principles of Buoyancy in Marine Fish Eggs and Their Vertical Distributions across the World Oceans

Science.gov (United States)

Sundby, Svein; Kristiansen, Trond

2015-01-01

for recruitment to the population. An example of adaptation to such conditions is Cape hake spawning above the critical layer in the Northern Benguela upwelling ecosystem. The eggs rise slowly in the onshore subsurface current below the Ekman layer, hence being advected inshore where the hatched larvae concentrate with optimal feeding conditions. PMID:26465149

Ambilpolar Electric Field and Diffusive Cooling of Electrons in Meteor Trails

Science.gov (United States)

Pasko, V. P.; Kelley, M. C.

2017-12-01

electric field and lose thermal energy. Under considered conditions electron heating in super elastic collisions with rotationally excited ambient molecules becomes important and we will illustrate related time scales by Monte Carlo simulations based on modeling framework of [Frost and Phelps, Phys. Rev., 127, 1621, 1962; Hake and Phelps, Phys. Rev., 158, 70, 1967].

A Holistic Approach to Fishery Management: Evidence and Insights from a Central Mediterranean Case Study (Western Ionian Sea

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Tommaso Russo

2017-06-01

Full Text Available The new Common Fisheries Policy (CFP is designed to represent an appropriate response to the uncertainties and challenges facing the fisheries sector. It also adopts a holistic approach to fisheries management, considering all factors driving fishers' behavior, and ultimately, the long-term maintenance of living resources. The most reliable way to pursue these aims could be represented by a change in the exploitation pattern, in order to guarantee the sustainability of fisheries without compromising their socioeconomic viability. In this paper, the demersal fisheries of the Ionian Sea [Geographic Sub-area (GSA 19] were analyzed with respect to their spatial, temporal, economic, and biological characteristics in terms of four key species for fisheries, namely European hake, red mullet, giant red shrimp, and deep-water rose shrimp. Specifically, (1 a quantitative procedure was applied to break down the whole system (including small-scale fleet components into a series of fishing grounds using input data about fishing efforts; (2 the different fleet segments were defined as a combination of main gear and fishing grounds; (3 the effort and production by fleet segment were derived according to biological samplings of commercial data (Data Collection Framework for the collection and management of fisheries data, DCF, information on localization of nursery and spawning grounds, and expert knowledge; and (4 all this information was used to feed a bioeconomic modeling tool (BEMTOOL, and to explore alternative exploitation patterns. A series of scenarios including the status quo were defined, starting from the actual management approach based on temporal fishing closure. The results showed that significant improvements in the exploitation pattern could be achieved by setting up spatial and/or temporal gear-specific bans of the fishing activity. More specifically, scenarios based on a 3-month fishing ban for trawlers are expected to provide high rebuilding

The mass balance of production and consumption: Supporting policy-makers for aquatic food security

Science.gov (United States)

Lopes, A. S.; Ferreira, J. G.; Vale, C.; Johansen, J.

2017-03-01

This work addresses divergences between data on consumption and availability for wild-caught and farmed fish, and normalisation of reported production data, to support integrated fisheries and aquaculture management. The methodologies developed, centred on improved parameterisation and on mass balance closure, were tested in two case studies: (i) the cod fishery in Europe, with particular emphasis on Iceland and the United Kingdom; and (ii) the overall balance of aquatic products for Portugal, the ICES member with the most diverse range of landed marine species. Data for consumption, Illegal, Unreported, or Unregulated (IUU) catch, and official availability statistics were used to identify discrepancies between consumption and official availability data. The identification of discrepancies between supply and demand, when coupled with source-discriminated data, showed a pattern where products with no unmet demand tend to display a considerable IUU percentage-above 9% in three cases (hake, sardine, and horse mackerel). By contrast with fished products with an over-met demand such as cod (144%) and sardine (124%), farmed species display low Optimal Consumption Level (OCL) satisfaction. Atlantic salmon, gilthead seabream, and European seabass register 45%, 58% and 44% respectively; this suggests a considerable unmet demand for these products and/or a high volume of undeclared fish reaching consumers, which may be due to the lack of landings control that exists for wild-caught fish. Improvements to production estimates using live-weight coefficients illustrate the impacts of seafood processing. Different processing methods can generate variations in live-weight estimates, leading to errors in officially reported data, and expose the limitations of the current statistical methods. As an example, the corrected per capita consumption for Portugal for 2014 (the latest FAO data) increases from 57 to 66 kg ind-1 y-1, which places the country as the second-greatest consumer in

The genomics of wild yeast populations sheds light on the domestication of man's best (micro) friend.

Science.gov (United States)

Eberlein, Chris; Leducq, Jean-Baptiste; Landry, Christian R

2015-11-01

The domestication of plants, animals and microbes by humans are the longest artificial evolution experiments ever performed. The study of these long-term experiments can teach us about the genomics of adaptation through the identification of the genetic bases underlying the traits favoured by humans. In laboratory evolution, the characterization of the molecular changes that evolved specifically in some lineages is straightforward because the ancestors are readily available, for instance in the freezer. However, in the case of domesticated species, the ancestor is often missing, which leads to the necessity of going back to nature in order to infer the most likely ancestral state. Significant and relatively recent examples of this approach include wolves as the closest wild relative to domestic dogs (Axelsson et al. 2013) and teosinte as the closest relative to maize (reviewed in Hake & Ross-Ibarra 2015). In both cases, the joint analysis of domesticated lineages and their wild cousins has been key in reconstructing the molecular history of their domestication. While the identification of closest wild relatives has been done for many plants and animals, these comparisons represent challenges for micro-organisms. This has been the case for the budding yeast Saccharomyces cerevisiae, whose natural ecological niche is particularly challenging to define. For centuries, this unicellular fungus has been the cellular factory for wine, beer and bread crafting, and currently for bioethanol and drug production. While the recent development of genomics has lead to the identification of many genetic elements associated with important wine characteristics, the historical origin of some of the domesticated wine strains has remained elusive due to the lack of knowledge of their close wild relatives. In this issue of Molecular Ecology, Almeida et al. (2015) identified what is to date the closest known wild population of the wine yeast. This population is found associated with

The relationship between cholesterol and cognitive function is homocysteine-dependent

Directory of Open Access Journals (Sweden)

Cheng YB

2014-10-01

Full Text Available Yibin Cheng,1 Yinlong Jin,1 Frederick W Unverzagt,2 Liqin Su,1 Lili Yang,3 Feng Ma,1 Ann M Hake,4,5 Carla Kettler,3 Chen Chen,1 Jingyi Liu,1 Jianchao Bian,6 Ping Li,7 Jill R Murrell,8 Hugh C Hendrie,2,9,10 Sujuan Gao3 1Institute for Environmental Health and Related Product Safety, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China; 2Department of Psychiatry, 3Department of Biostatistics, 4Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana, USA; 5Eli Lilly and Company, Indianapolis, Indiana, USA; 6Shandong Institute for Prevention and Treatment of Endemic Disease in China, Jinan, People’s Republic of China; 7Sichuan Provincial Center for Disease Control and Prevention in China, Chengdu, People’s Republic of China; 8Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, 9Indiana University Center for Aging Research, 10Regenstrief Institute, Inc., Indianapolis, Indiana, USA Introduction: Previous studies have identified hyperlipidemia as a potential risk factor for dementia and Alzheimer’s disease. However, studies on cholesterol measured in late-life and cognitive function have been inconsistent. Few studies have explored nonlinear relationships or considered interactions with other biomarker measures.Methods: A cross-sectional sample of 1,889 participants from four rural counties in the People’s Republic of China was included in this analysis. Serum total cholesterol, high-density lipoprotein, triglycerides, and homocysteine levels were measured in fasting blood samples. A composite cognitive score was derived based on nine standardized cognitive test scores. Analysis of covariance models were used to investigate the association between biomarker measures and the composite cognitive scores.Results: There was a significant interaction between the homocysteine quartile group and the cholesterol quartile group on cognitive scores (P=0

Marine biodiversity in South Africa: an evaluation of current states of knowledge.

Directory of Open Access Journals (Sweden)

Charles L Griffiths

Full Text Available Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ of just over 1 million km(2. Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and well-curated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System data center (which stores data from a wider African region. A large number of regional guides to the marine fauna and flora are also available and are listed. The currently recorded marine biota of South Africa numbers at least 12,914 species, although many taxa, particularly those of small body size, remain poorly documented. The coastal zone is relatively well sampled with some 2,500 samples of benthic invertebrate communities have been taken by grab, dredge, or trawl. Almost none of these samples, however, were collected after 1980, and over 99% of existing samples are from depths shallower than 1,000 m--indeed 83% are from less than 100 m. The abyssal zone thus remains almost completely unexplored. South Africa has a fairly large industrial fishing industry, of which the largest fisheries are the pelagic (pilchard and anchovy and demersal (hake sectors, both focused on the west and south coasts. The east coast has fewer, smaller commercial fisheries, but a high coastal population density, resulting in intense exploitation of inshore resources by recreational and subsistence fishers, and this has resulted in the overexploitation of many coastal fish and invertebrate stocks. South Africa has a small aquaculture industry rearing mussels, oysters, prawns, and abalone-the latter two in land-based facilities. Compared with many other developing countries, South Africa has a well

2013-2014 California Current Ecosystem (CCE14): Acoustic-Trawl Survey of Coastal Pelagic Fishes (Legs I and II); and Investigations of hake survey methods, life history, and associated ecosystem (Legs III and IV) (SH1405, EK60)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The 2014 acoustic-trawl method (ATM) project aboard Bell M. Shimada represents a joint effort between the SWFSC and the NWFSC in investigating elements of the...

2013-2014 California Current Ecosystem (CCE14): Acoustic-Trawl Survey of Coastal Pelagic Fishes (Legs I and II); and Investigations of hake survey methods, life history, and associated ecosystem (Legs III and IV) (SH1405, ME70)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The 2014 acoustic-trawl method (ATM) project aboard Bell M. Shimada represents a joint effort between the SWFSC and the NWFSC in investigating elements of the...

Trophic modeling of the Northern Humboldt Current Ecosystem, Part I: Comparing trophic linkages under La Niña and El Niño conditions

Science.gov (United States)

Tam, Jorge; Taylor, Marc H.; Blaskovic, Verónica; Espinoza, Pepe; Michael Ballón, R.; Díaz, Erich; Wosnitza-Mendo, Claudia; Argüelles, Juan; Purca, Sara; Ayón, Patricia; Quipuzcoa, Luis; Gutiérrez, Dimitri; Goya, Elisa; Ochoa, Noemí; Wolff, Matthias

2008-10-01

The El Niño of 1997-98 was one of the strongest warming events of the past century; among many other effects, it impacted phytoplankton along the Peruvian coast by changing species composition and reducing biomass. While responses of the main fish resources to this natural perturbation are relatively well known, understanding the ecosystem response as a whole requires an ecotrophic multispecies approach. In this work, we construct trophic models of the Northern Humboldt Current Ecosystem (NHCE) and compare the La Niña (LN) years in 1995-96 with the El Niño (EN) years in 1997-98. The model area extends from 4°S-16°S and to 60 nm from the coast. The model consists of 32 functional groups of organisms and differs from previous trophic models of the Peruvian system through: (i) division of plankton into size classes to account for EN-associated changes and feeding preferences of small pelagic fish, (ii) increased division of demersal groups and separation of life history stages of hake, (iii) inclusion of mesopelagic fish, and (iv) incorporation of the jumbo squid ( Dosidicus gigas), which became abundant following EN. Results show that EN reduced the size and organization of energy flows of the NHCE, but the overall functioning (proportion of energy flows used for respiration, consumption by predators, detritus and export) of the ecosystem was maintained. The reduction of diatom biomass during EN forced omnivorous planktivorous fish to switch to a more zooplankton-dominated diet, raising their trophic level. Consequently, in the EN model the trophic level increased for several predatory groups (mackerel, other large pelagics, sea birds, pinnipeds) and for fishery catch. A high modeled biomass of macrozooplankton was needed to balance the consumption by planktivores, especially during EN condition when observed diatoms biomass diminished dramatically. Despite overall lower planktivorous fish catches, the higher primary production required-to-catch ratio implied a

Cost efficiency and ressource efficiency in the waste management. Proceedings; Kosten- und Ressourceneffizienz in der Abfallwirtschaft. Tagungsband

Energy Technology Data Exchange (ETDEWEB)

Fricke, K. [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[Technische Univ. Braunschweig (Germany). Lehrstuhl fuer Abfall- und Ressourcenwirtschaft; Bergs, C.G. [Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Berlin (Germany); Kosak, G. [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[IBK-Kosak GmbH, Neustadt/Weinstrasse (Germany); Wallamnn, R. (eds.) [Arbeitskreis fuer die Nutzbarmachung von Siedlungsabfaellen (ANS) e.V., Braunschweig (Germany)]|[IGW Ingenieurgemeinschaft Witzenhausen Fricke und Turk GmbH (Germany)

2007-07-01

Uphoff); (s) An economical optimisation of existing composting plants by means of energetical use of sectional flows (T. Turk, M. Idelmann, J. Hake); (t) Conditioning of biomass from biological wastes: A cost efficient and resource efficient solution? (J. Dach, S. Bode, A. Warnstedt, G. Mueller); (u) Implementation of fermentation in the utilization of biological waste and treatment of residual wastes (K. Fricke, T. Bahr); (v) Enhancement of the energy efficiency of composting plants such as Kompostwerk Goettingen GmbH (K. Loewe, O. Ruehl, M. Nelles, S. Prechtl, R. Scholz); (w) Measures for treatment of processing water and drainage water during fermentation of waste materials - what can the waste management learn from the residential water management? (N. Dichtl, L. Guenther, S. Wolter); (x) Management of material transport of biological wastes with the aim: Optimization of utilization of organic wastes (F. Knappe).

Connecting research discovery with care delivery in dementia: the development of the Indianapolis Discovery Network for Dementia

Directory of Open Access Journals (Sweden)

Boustani MA

2012-11-01

Full Text Available Malaz A Boustani,1–3 Amie Frame,1,2 Stephanie Munger,1,2 Patrick Healey,4 Jessie Westlund,5 Martin Farlow,6,7 Ann Hake,8 Mary Guerriero Austrom,6,9 Polly Shepard,10 Corby Bubp,10 Jose Azar,3 Arif Nazir,3 Nadia Adams,11 Noll L Campbell,1,2,12,13 Azita Chehresa,5 Paul Dexter2,31Indiana University Center for Aging Research, 2Regenstrief Institute, Inc, 3Department of Medicine, Indiana University School of Medicine (IUSM, 4St Vincent Health Network, 5Community Health Network, 6Indiana Alzheimer Disease Center, IUSM, 7Department of Neurology, IUSM, 8Eli Lilly and Company, 9Department of Psychiatry, IUSM, 10The Memory Clinic of Indianapolis, 11Indiana University Health, Indianapolis, IN, USA; 12Department of Pharmacy Practice, Purdue University College of Pharmacy, West Lafayette, IN, USA; 13Department of Pharmacy, Wishard Health Services, Indianapolis, IN, USABackground: The US Institute of Medicine has recommended an integrated, locally sensitive collaboration among the various members of the community, health care systems, and research organizations to improve dementia care and dementia research.Methods: Using complex adaptive system theory and reflective adaptive process, we developed a professional network called the “Indianapolis Discovery Network for Dementia” (IDND. The IDND facilitates effective and sustainable interactions among a local and diverse group of dementia researchers, clinical providers, and community advocates interested in improving care for dementia patients in Indianapolis, Indiana.Results: The IDND was established in February 2006 and now includes more than 250 members from more than 30 local (central Indiana organizations representing 20 disciplines. The network uses two types of communication to connect its members. The first is a 2-hour face-to-face bimonthly meeting open to all members. The second is a web-based resource center (http://www.indydiscoverynetwork.org. To date, the network has: (1 accomplished the

Feminist Physics Education: Deconstructed Physics and Students' Multiple Subjectivities

Science.gov (United States)

Jammula, Diane Crenshaw

Physics is one of the least diverse sciences; in the U.S. in 2010, only 21% of bachelors degrees in physics were awarded to women, 2.5% to African Americans, and 4% to Hispanic Americans (AIP, 2012). Though physics education reform efforts supporting interactive engagement have doubled students' learning gains (Hake, 1998), gender and race gaps persist (Brewe et al., 2010; Kost, Pollock, & Finkelstein, 2009). When students' subjectivities align with presentations of physics, they are more likely to develop positive physics identities (Hughes, 2001). However, both traditional and reformed physics classrooms may present physics singularly as abstract, elite, and rational (Carlone, 2004). Drawing from feminist science, I argue that binaries including abstract / concrete, elite / accessible, and rational / emotional are hierarchal and gendered, raced and classed. The words on the left define conventional physics and are associated with middle class white masculinity, while the words on the right are associated with femininity or other, and are often missing or delegitimized in physics education, as are females and minorities. To conceptualize a feminist physics education, I deconstructed these binaries by including the words on the right as part of doing physics. I do not imply that women and men think differently, but that broadening notions of physics may allow a wider range of students to connect with the discipline. I used this conceptual framework to modify a popular reformed physics curriculum called Modeling Instruction (Hestenes, 1987). I taught this curriculum at an urban public college in an introductory physics course for non-science majors. Twenty-three students of diverse gender, race, ethnic, immigrant and class backgrounds enrolled. I conducted an ethnography of the classroom to learn how students negotiate their subjectivities to affiliate with or alienate from their perceptions of physics, and to understand how classroom experiences exacerbate or

Concentração e retenção do selênio em peixes marinhos Concentration and retention of selenium in marine fish

Directory of Open Access Journals (Sweden)

Alfredo Tenuta Filho

2010-05-01

average levels of Se found in bony fish, gutted corvina (Micropogonias furnieri, triggerfish (Balistes capricus, hake and sardine (Sardinella brasiliensis, 0.48 ± 0.18 μg.g-1, and in cartilaginous fish, small shark (squantina Guggenheim, hammerhead shark, spinner shark, and sand tiger shark, 0.36 ± 0.07 μg.g-1, did not differ from one another (p > 0.05. In fact, their occurrence was in accordance with the literature data on marine fish. The levels of Se found in the sharks (predatory species are not enough to establish a stoichiometric relation for the interaction with Hg focusing on the desired toxic protection. The effective Se retention evaluated in the sand tiger shark, after extraction with water, was considered high (minimum of 68.81% and important taking nutritional and toxicological aspects into account.