Methods of feeding of some macrothricids (Cladocera, Macrothricidae). [Translation from: Informatsionnyi Byulleten Biologiya Vnutrennikh Vod 16, 29-34, 1973.]

The feeding methods of macrothricids was investigated in three species — Ophryoxus gracilis G.O. Sars, Ilyocryptus sordidus (Lievin) and Lathonura rectirostris O.F.Muller. The procuring of food in those species follows two methods: filtration of dispersed particles or scraping off and collecting food from the surface of the substrate. When collecting food by scraping off is the sole method of feeding (as in Lathonura rectirostris), movement along the substrate and feeding are combined so intimately that they appear as parts of one and the same mechanism.

Cultivation methods for Lemnaceae [Translation from: Wiadomosci Botaniczne 7(2) 153-164, 1963]

Representatives from the family of Lemnaceae (duckweed) make ideal experimental material for research into a succession of phytophysiological processes with regard to growth rate and vegetative reproduction. They are also easy to maintain in sterile cultures. Lemnaceae belong to the higher flowering plants (flowers are rarely produced), however they are distinguished by a much simplified morphological and anatomical structure. As water plants they possess the advantage, that they can be cultivated in synthetic media under laboratory conditions controlled by the application of both a known light intensity and temperature. This paper describes experimental research of growth of Lemnaceae in different conditions. Some of the variables were mineral media, illumination and aeration.

Preliminary Analysis of the Feasibility of Transferring New Longline Technology to Small Artisanal Vessels off Northeastern Brazil

The catches of three longliners, including two recently converted small artisanal vessels and one large leased foreign longliner, were compared to provide some indication of the feasibility of transferring new longline technology to small vessels in the northeastern Brazilian pelagic longline fishery. Comparisons of catches between the two recently converted vessels operating across the same spatial and temporal scales showed no significant differences for the main target species, providing evidence to suggest that adoption of the technology was rapid and straightforward. A comparison of relative catch rates between one of the recently converted small longliners and the leased longliner across the same temporal scale, but in different areas, showed that while there were significant differences detected for some species, contributing to a significant reduction in total CPUE, the relative abundance of commercially important species within the operational range of the smaller vessels was sufficient for economically viable catches. The results showed that the net financial profit from the artisanal longliner was almost 10 times greater than that derived from existing fishing methods. The inclusion of some artisanal vessels in this fishery may help address the social and economic problems currently faced by fi

Improved chemical methods for extraction of fin rays from shark fins

A survey was undertaken of methods available for the extraction of fin rays from shark fins. The development of new, quicker and easier methods of processing is presented.

Species identification and authentication of some of the most important seafood products in Iranian markets using biotechnological methods based on DNA

This study describes the molecular identification of sixteen fish species present in processed products imported into Iran for human consumption. DNA barcoding using direct sequencing of about 650 bp of the mitochondrial Cytochrome Oxidase subunit I gene revealed incorrect labeling (31.25%). Substitution of fish species constitutes serious economic fraud, and our results increase concern regarding the trading of processed fish products in Iran from both health and conservation points of view.