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Deadliest Catch, Terra Australis Edition
Get PDFPeople are very familiar with Northern Hemisphere crabfisheries, to the point where there is a popular TV series aboutthem (Deadliest Catch). However, king crab fisheries in theSouthern Hemisphere are almost unknown, although theypossess many of the characteristics that have made northernfisheries famous: remote fishing areas, rough and cold seas,bad weather, and a resource of high economic value. Here, wereview the history of southern king crab fisheries at the ?endof the world? and describe the current fishery in Patagonia.Fil: Varisco, Martin Alejandro. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Colombo, Julia Soledad. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vinuesa, Julio Hector. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentin
Differences in the timing of egg extrusion and reproductive investment between primiparous and multiparous females of the southern king crab Lithodes santolla
No full textThis study analysed differences in the timing of egg extrusion, reproductive investment and spatial distribution between primiparous and multiparous females of the southern king crab (SKC) Lithodes santolla. Early publications had reported that, in the San Jorge Gulf (SJG; 45–47°S), Argentina, SKCs mated annually, mainly in December. In this work, in coastal areas of SJG, we found small females in postmoult with recently extruded eggs in September–October. At the same time, one SKC female fraction was in intermoult with eggs close to hatching. Evidence suggests that females with recently extruded eggs were primiparous, while females with eggs close to hatching were multiparous. Primiparous females were less fecund than multiparous females of the same size, but no differences were found in the egg dry mass between these female fractions. The size-frequency distribution observed suggests a spatial segregation between primiparous and multiparous females, with the former being concentrated in the coastal areas of SJG. Differences in reproductive traits between primiparous and multiparous females have been widely reported in crab species with determinate growth, but rarely in crabs with indeterminate growth as lithodids.Fil: Colombo, Julia Soledad. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Blandi, Ayelen. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro; ArgentinaFil: Lértora, Hugo Pablo. Instituto Nacional de Investigaciones y Desarrollo Pesquero; ArgentinaFil: Varisco, Martin Alejandro. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; Argentin
Aggregation patterns in juvenile southern king crab Lithodes santolla (Molina, 1782): Are the aggregations related to moulting activity?
No full textThe early life history of decapod species involves several stages and ontogeny-related shifts in habitat requirements and behaviour. Early publications have reported that, in the San Jorge Gulf (45–47°S), Argentina, juvenile southern king crab Lithodessantolla (Molina, 1782) (SKC) remain in rocky coastal habitats for at least three years, prior to their migration to soft bottoms. In this study, we analysed the gregarious behaviour of juvenile SKCs and its relation with moulting activity through the early ontogeny of the species. Different aggregation patterns were observed in SKC juveniles during sampling. These aggregation patterns were related to an increase in moulting activity. SKC 1+ and 2+ formed small groups of 7–31 juveniles in holes or cracks at shallower depths. A large aggregation was recorded in November 2014 associated with Macrocystis pyrifera forests. This aggregation involved advanced juveniles 3+, probably at the end of their stay in the coastal environment. Our results suggest that the aggregation of juvenile SKCs is related to high moulting activity and that differences in the aggregation patterns are related to ontogeny. The aggregation of advanced juveniles may reflect a (re)synchronous moult prior to a coordinated abandonment of the coastal environment.Fil: Colombo, Julia Soledad. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia "san Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz; ArgentinaFil: Vinuesa, Julio Hector. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia "san Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco"; ArgentinaFil: Varisco, Martin Alejandro. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz | Universidad Nacional de la Patagonia "san Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge. Centro de Investigaciones y Transferencia Golfo San Jorge: Sede Caleta Olivia - Santa Cruz; Argentin
Growth and maturity of the spider crab Halicarcinus planatus (Brachyura: Hymenosomatidae) females in the southwestern Atlantic Ocean. Can these parameters be influenced by the population sex ratio?
Get PDFThe Halicarcinus planatus populations of the southwestern Atlantic Ocean show a highly variable sex ratio and a large size overlapping between females in the last immature instar (ADO) and mature (MAT) females. We hypothesized that these facts are related and that female impregnation has a central role in this relation. Non-impregnated ADO females delay maturity and would continue to grow, leading to size overlapping. This scenario is most probable in populations with a scarcity of males and could affect the growth, maturity and population structure. The sex ratio and female size distribution of several populations of the southwestern Atlantic Ocean were analysed. Growth and maturity were studied in two populations with different sex ratios (Camarones, a population with males, and Rada Tilly, a population where no males were found). Size overlapping was not related to the population sex ratio. Size overlapping was due to a variable moult increment and, to a lesser extent, to delayed maturity. Females mated before terminal moult in both populations. However, in Camarones, physiological maturity was not related to impregnation, while in Rada Tilly, vitellogenic oocytes were observed only in impregnated females. Also, differences in the number of spermatophores in female spermathecae were related to the sex ratio. Our results showed that the morphological maturity pattern of females was not influenced by the population sex ratio. However, physiological maturity was related to female impregnation and sex ratio. Also, the variation in the number of spermatophores suggests differences in the mating system related to the sex ratio.Fil: Varisco, Martin Alejandro. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia ; ArgentinaFil: Colombo, Julia Soledad. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia ; ArgentinaFil: Isola, Tomas. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia ; ArgentinaFil: Vinuesa, Julio Hector. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia ; Argentin
Proximate Composition and Nutritional Quality of the Meat of the Squat Lobster Munida gregaria (Fabricius 1973)
No full textThe squat lobster Munida gregaria has been recognized as a potential resource in several countries. However, data about its composition and nutritional value are scarce. This study provides information about the nutrients and nutritional quality of M. gregaria meat. Meat yield, proximate composition, cholesterol content, and fatty acid (FA) and amino acid (AAs) profiles were analyzed, and nutritional quality indexes were estimated. The average meat yield was 9.93%. The yearly average of the proximate composition of the M. gregaria meat (g/100 g meat) was moisture = 77.6, protein = 13.7, lipids = 3.84, and ash = 2.19. The average annual cholesterol content was 6.60 mg/100 g. The predominant FA (%) was C20:5ω3 (23.6), followed by C18:1ω9c (20.9), C22:6ω3 (18.5), and C16:0 (16.3); the unsaturated fatty acids were 72.8% of the total FA. The main AAs (g/100 g protein) were glutamic acid (15.1), leucine (9.47), and aspartic acid (8.51). Regarding the nutritional quality, the polyunsaturated FA/saturated FA ratio (1.99), ω3/ω6 ratio (8.62), atherogenic index (0.26), thrombotic index (0.56), hypocholesterolemic/hypercholesterolemic ratio (4.07), and polyene index (2.58) showed that M. gregaria meat provides lipids that are beneficial to the human diet. Moreover, M. gregaria meat provides high-quality proteins, which are well balanced in their essential AAs composition.Fil: Varisco, Martin Alejandro. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Crovetto, Cecilia. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro. Departamento de Bioquímica; ArgentinaFil: Colombo, Julia Soledad. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Vinuesa, Julio Hector. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia Golfo San Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia Golfo San Jorge. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigaciones y Transferencia Golfo San Jorge; ArgentinaFil: Risso, Susana Josefina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Comodoro. Departamento de Bioquímica; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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