976 resultados para background deep sea


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Mining seafloor massive sulfides for metals is an emergent industry faced with environmental management challenges. These revolve largely around limits to our current understanding of biological variability in marine systems, a challenge common to all marine environmental management. VentBase was established as a forum where academic, commercial, governmental, and non-governmental stakeholders can develop a consensus regarding the management of exploitative activities in the deep-sea. Participants advocate a precautionary approach with the incorporation of lessons learned from coastal studies. This workshop report from VentBase encourages the standardization of sampling methodologies for deep-sea environmental impact assessment. VentBase stresses the need for the collation of spatial data and importance of datasets amenable to robust statistical analyses. VentBase supports the identification of set-asides to prevent the local extirpation of vent-endemic communities and for the post-extraction recolonization of mine sites. © 2013.

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The interaction between microorganisms and host defense mechanisms is a decisive factor for the survival of marine bivalves. They rely on cell-mediated and humoral reactions to overcome the pathogens that naturally occur in the marine environment. In order to understand host defense reactions in animals inhabiting extreme environments we investigated some of the components from the immune system of the deep sea hydrothermal vent mussel Bathymodiolus azoricus. Cellular constituents in the hemolymph and extrapallial fluid were examined and led to the identification of three types of hemocytes revealing the granulocytes as the most abundant type of cell. To further characterize hemocyte types, the presence of cell surface carbohydrate epitopes was demonstrated with fluorescent WGA lectin, which was mostly ascribed to the granulocytes. Cellular reactions were then investigated by means of phagocytosis and by the activation of putative MAPKs using the microbial compounds zymosan, glucan, peptidoglycan and lipopolysaccharide. Two bacterial agents, Bacillus subtilis and Vibrio parahaemolyticus, were also used to stimulate hemocytes. The results showed that granulocytes were the main phagocytic cells in both hemolymph and extrapallial fluid of B. azoricus. Western blotting analyses using commercially available antibodies against ERK, p38 and JNK, suggested that these putative kinases are involved in signal transduction pathways during experimental stimulation of B. azoricus hemocytes. The fluorescent Ca2+ indicator Fura-2 AM was also insightful in demonstrating hemocyte stimulation in the presence of laminarin or live V. parahaemolyticus. Finally, the expression of the antibacterial gene mytilin was analyzed in gill tissues by means of RT-PCR and whole-mount in situ hybridization. Mytilin transcripts were localized in hemocytes underlying gill epithelium. Moreover, mytilin was induced by exposure of live animals to V. parahaemolyticus. These findings support the premise of a conserved innate immune system in B. azoricus. Such system is comparable to other Bivalves and involves the participation of cellular and humoral components. © 2008 Elsevier Inc. All rights reserved.

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Seafloor massive sulfide (SMS) mining will likely occur at hydrothermal systems in the near future. Alongside their mineral wealth, SMS deposits also have considerable biological value. Active SMS deposits host endemic hydrothermal vent communities, whilst inactive deposits support communities of deep water corals and other suspension feeders. Mining activities are expected to remove all large organisms and suitable habitat in the immediate area, making vent endemic organisms particularly at risk from habitat loss and localised extinction. As part of environmental management strategies designed to mitigate the effects of mining, areas of seabed need to be protected to preserve biodiversity that is lost at the mine site and to preserve communities that support connectivity among populations of vent animals in the surrounding region. These "set-aside" areas need to be biologically similar to the mine site and be suitably connected, mostly by transport of larvae, to neighbouring sites to ensure exchange of genetic material among remaining populations. Establishing suitable set-asides can be a formidable task for environmental managers, however the application of genetic approaches can aid set-aside identification, suitability assessment and monitoring. There are many genetic tools available, including analysis of mitochondrial DNA (mtDNA) sequences (e.g. COI or other suitable mtDNA genes) and appropriate nuclear DNA markers (e.g. microsatellites, single nucleotide polymorphisms), environmental DNA (eDNA) techniques and microbial metagenomics. When used in concert with traditional biological survey techniques, these tools can help to identify species, assess the genetic connectivity among populations and assess the diversity of communities. How these techniques can be applied to set-aside decision making is discussed and recommendations are made for the genetic characteristics of set-aside sites. A checklist for environmental regulators forms a guide to aid decision making on the suitability of set-aside design and assessment using genetic tools. This non-technical primer document represents the views of participants in the VentBase 2014 workshop.

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Dissertação de Mestrado, Estudos Integrados dos Oceanos, 25 de Julho 2013, Universidade dos Açores.

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Tese de Doutoramento em Ciências do Mar, especialidade em Ecologia Marinha.

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Tese de Doutoramento, Ciências do Mar, especialidade de Biologia Marinha, 18 de Dezembro de 2015, Universidade dos Açores.

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Tese de Doutoramento, Ciências do Mar, especialidade de Biologia Marinha, 19 de Dezembro de 2015, Universidade dos Açores.

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School Of Industrial Fisheries, Cochin University of Science and Technology

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With a seacoast of 8,1 18 km, an exclusive economic zone (EEZ) of 2 million square km, and with an area of about 30,000 square km under aquaculture, lndia produces close to six million tonnes of fish, over 4 per cent of the world fish production. While the marine waters upto 50m depth have been fully exploited, those beyond, remain unexplored. There is an ever increasing demand for fishery resources as food. The coastal fishery resources of the country are dwindling at a rapid pace and it becomes highly imperative that we search for alternate fishery resources for food. The option we have is to hunt for marine fishery resources. Studies pertaining to proximate composition, amino acid and fatty acid composition are essential to understand the nutraceutical values of these deep sea fishery resources. The present study was aimed to carry out proximate composition of deep sea fishery resources obtained during cruises onboard the FORV Sarise Sampada, to identify fishery resources which have appreciable lipid content and thereby analyse the bioactive potentials of marine lipids, to study the amino acid profile of these fishery resources, to understand the contents of SPA, MUFA and PUFA and to calculate the n3/n6 fatty acid contents. Though the presence of nutraceuticals was identified in the marine fishery resources their use as potential food resources deserve further investigation. So the study were carried out to calculate the hepatosomatic indices of sharks & chimaeras and conduct biochemical characterisation of liver oils of Apristurus indicus, Cenlrophorus scalprams, Centroselachus crepidater, Neoharriotta raleighana, and Harriotta pinnata obtained during cruises onboard the FORV Sugar Sampada.Therapeutic use of shark liver oil is evident from its use for centuries as a remedy to heal wounds and fight flu (Neil er al. 2006). Japanese seamen called it 'samedava' or "cure all". Shark liver oil is being promoted worldwide as a dietary supplement to boost the immune system, fight infections, to treat cancer and to lessen the side effects of conventional cancer treatment. These days more emphasis is laid on the nutritive benefits of shark liver oils especially on the omega 3 polyunsaturated fatty acids ( PUFAs) (Anandan er al. 2007) and alkylglycerols (AKGs) (Pugliese er al. I998) contained in them due to the high rise of inflammatory disorders such as arthritis, asthma and neurodegenerative diseases like Alzheimer’s, Parkinson’s and Schizophrenia. So the present study also evaluate the pharmacological properties with respect to analgesic, anti-inflammatory, anti pyretic and anti-ulcer effects of four different liver oils of sharks belonging to the Indian EEZ and to identify the components of oil responsible for these activities.The analgesic and anti-inflammatory activities of liver oils from Neoharriotra raleighana (NR), Centrosymnus crepidater (CC), Apristurus indicus (AI), and Centrophorus sculpratus (CS) sharks caught from the Arabian Sea and the Indian Ocean were compared. The main objectives also include determination of the cholesterol lowering effects of liver oils of Neoharriotra raleighana (NR) and Centrophorus sculpratus (CS) on the high fat diet induced dyslipidemia and to compare the impact of four isolipidemic diets, on levels of serum diagnostic marker enzymes, on lipid profile of blood and liver and antioxidant status of heart in male Albino rats. And also to study the efficacy of Centrophorus sculpratus (CS) liver oil against Complete Freund’s Adjuvant-induced arthritis and to compare the anti-inflammatory activity of this oil with a traditionally used anti-inflammatory substance gingerol (oleoresin extracted from ginger.). The results of the present study indicated that both (Centrophorus sculpratus liver oils as well as gingerol extracts proved to be effective natural remedies against CFA-induced arthritis in Albino rats.

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This thesis Entitled distribution ,diversity and biology of deep-sea fishes the indian Eez.Fishing rights and responsibilities it entails in the deep-sea sector has been a vexed issue since the mid-nineties and various stakeholders have different opinion on the modalities of harnessing the marine fisheries wealth, especially from the oceanic and deeper waters. The exploitation and utilization of these esources requires technology development and upgradation in harvest and post-harvest areas; besides shore infrastructure for berthing, handling, storing and processing facilities. At present, although deep-sea fishes don’t have any ready market in our country it can be converted into value added products. Many problems have so far confronted the deep-sea fishing sector not allowing it to reach its full potential. Hence, there should be a sound deep-sea fishing policy revolving round the upgradation of the capabilities of small scale fishermen, who have the inherent skills but do not have adequate support to develop themselves and to acquire vessels having the capability to operate in farther and deeper waters. Prospects for the commercial exploitation and utilization of deep-sea fishes were analyzed using SWOL analysis.

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Hepcidin is cysteine-rich short peptide of innate immune system of fishes, equipped to perform prevention and proliferation of invading pathogens like bacteria and viruses by limiting iron availability and activating intracellular cascades. Hepcidins are diverse in teleost fishes, due to the varied aquatic environments including exposure to pathogens, oxygenation and iron concentration. In the present study, we report a 87-amino acid (aa) preprohepcidin (Hepc-CB1) with a signal peptide of 24 aa, a prodomain of 39 aa and a bioactive mature peptide of 24 aa from the gill mRNA transcripts of the deep-sea fish spinyjaw greeneye, Chlorophthalmus bicornis. Molecular characterisation and phylogenetic analysis categorised the peptide to HAMP2-like group with a mature peptide of 2.53 kDa; a net positive charge (?3) and capacity to form b-hairpin-like structure configured by 8 conserved cysteines. The present work provides new insight into the mass gene duplication events and adaptive evolution of hepcidin isoforms with respect to environmental influences and positive Darwinian selection. This work reports a novel hepcidin isoform under the group HAMP2 from a nonacanthopterygian deep-sea fish, C. bicornis

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Elasmobranchs comprising sharks, skates and rays have traditionally formed an important fishery along the Indian coast. Since 2000, Indian shark fishermen are shifting their fishing operations to deeper/oceanic waters by conducting multi-day fishing trips, which has resulted in considerable changes in the species composition of the landings vis- a-vis those reported during the 1980’s and 1990’s. A case study at Cochin Fisheries Harbour (CFH), southwest coast of India during 2008-09 indicated that besides the existing gillnet–cum- hooks & line and longline fishery for sharks, a targeted fishery at depths >300-1000 m for gulper sharks (Centrophorus spp.) has emerged. In 2008, the chondrichthyan landings (excluding batoids) were mainly constituted by offshore and deep-sea species such as Alopias superciliosus (24.2%), Carcharhinus limbatus (21.1%), Echinorhinus brucus (8.2%), Galeocerdo cuvier (5.4%), Centrophorus spp. (7.3%) and Neoharriotta pinnata (4.2%) while the contribution by the coastal species such as Sphyrna lewini (14.8%), Carcharhinus sorrah (1.4%) and other Carcharhinus spp. has reduced. Several deep-sea sharks previously not recorded in the landings at Cochin were also observed during 2008-09. It includes Hexanchus griseus, Deania profundorum, Zameus squamulosus and Pygmy false catshark (undescribed) which have been reported for the first time from Indian waters. Life history characteristics of the major fished species are discussed in relation to the fishery and its possible impacts on the resource

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The present study is the first attempt to understand population characteristics of the deep-sea pandalid shrimp, P. quasigrandis and to assess the status of these resources off Kerala coast.Total mortality coefficient (Z) of P. quasigrandis estimated by various methods.Natural mortality coefficient (M) calculated was 0.65 and 1.02 by Pauly‟sempirical formula and Srinaths‟s formula respectively The deep-sea shrimp P. quasigrandis exploited from the present fishing ground and their monetary return has started showing a declining trend. By observing the current yield and economic return, there is no further scope for increasing the catch from the present fishing ground. The study indicated that majority of the deep-sea shrimp trawlers, especially targeted for pandalid shrimps still concentrated off Kollam area (Quilon Bank). Even though researchers had located several potential deep-sea fishing grounds based on exploratory surveys in Indian EEZ , fishermen are unaware of these fishing grounds located and hence sharing the information about new potential deep-sea fishing grounds could avert the possible stock decline due to the intensive targeted deep-sea shrimp fishery in the Quilon Bank. Hence, the present study recommended that part of the effort from existing fishing grounds may be shifted to newly located deep-sea fishing grounds which will help in a sustainableexploitation of deep-sea resources off Kerala coast.

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Available information on abundance of myctophids and their utilisation indicate that there is excellent scope for development of myctophid fisheries in Indian Ocean. Most of the conventional fish stocks have reached a state of full exploitation or over-exploitation. Hence there is need to locate new and conventional fishery resources in order to fill in the supply-demand gap, in the face of increasing demand for fish. Information on length-weight relationship, age and growth, spawning season, fecundity and age at maturity and information on bycatch discards are required for sustainable utilization of myctophid resource in the Indian Ocean