1,720,996 research outputs found
Diamanti Ilvo : Bianco, rosso, verde...e azzurro. Mappe e colori dell'Italia politica
No full textRoux Christophe. Diamanti Ilvo : Bianco, rosso, verde...e azzurro. Mappe e colori dell'Italia politica. In: Pôle Sud, n°21, 2004. pp. 130-132
Diamanti Ilvo : Bianco, rosso, verde...e azzurro. Mappe e colori dell'Italia politica
No full textRoux Christophe. Diamanti Ilvo : Bianco, rosso, verde...e azzurro. Mappe e colori dell'Italia politica. In: Pôle Sud, n°21, 2004. pp. 130-132
Annual sex steroid levels in cultured dusky grouper females
No full textThe dusky grouper Epinephelus marginatus is a proteroginic hermaphrodite that exhibits a complex reproductive biology. Under captive condition most females do not proceed into vitellogenesis and do not spawn spontaneously. Sex-steroids profiles during the reproductive cycle have been recently studied in the wild (Marino et a. 1997), but no data are available on sex steroids levels in cultured fish. This study describes the seasonal variation of 17ß-estradiol (E2) and testosterone (T), 11-ketotestosterone (11-KT) and 11ß hydroxyandrostenedione (OHA) plasma levels in dusky grouper females
Induced spawning and first larval rearing in Epinephelus marginatus
No full textMethods for controlled breeding of tropical groupers have been developed from 1977, but no reliable techniques are available for mediterranean groupers. From 1995 up to 1998 several trials for hormonal induction of final maturation and spawning have been tested on wild dusky grouper females (body weight 2.2-10.1 Kg ) adapted to captivity. Three broodstocks were maintained under natural photoperiod applying both natural and controlled thermoperiods. Fish with vitellogenic oocytes (>350 m) were induced (n=8) both with Human Chorionic Gonadotropin (HCG) at 500-2000 UI/Kg dosage, given in multiple injections, and with HCG (2000 UI/Kg) in combination with sea bass pituitary (7-9mg/Kg). HCG partially mimicked natural gonadotropin, inducing ovulation only in synergy with pituitary. GnRHa-Dep in microspheres (Triptoreline, Decapeptyl, Ipsen Biotech) at 40-50 g/Kg induced multiple spawning in 50% of females (n=26) with oocytes >350 m. Vitellogenic oocytes 350 m were not sensitive to HCG, pituitary extracts, GnRHa and GnRHa-Dep.
Ovulation time ranged between 66-85 hours, according to temperature (17.7°C- 24.2°C) and oocyte maturity stage. Natural ovulation of healthy eggs was never achieved. Fertilisation rate on viable stripped eggs ranged between 80-89.5%. Embryonic development lasted 50-52.5 hours and survival at hatching (100%) varied widely (0-90.9 %). Mean eggs diameter was 839 9.9 m and mean dry weight was approximately 66 g. Preliminary larval rearing trials were carried out in 500l incubators using green algae, cryopreserved oyster trochophores (30 ind/ml) and baby rotifers (Brachionus plicatilis, size 80-90 m, 30 ind/ml). Survival was approximately 90% after 12 days from hatching. The first critical period was observed between 13th-15th days with 100% mortality. Further studies to identify physiological, metabolic and trophic parameters are necessary to set up reliable larval rearing techniques
Induced sex change of dusky grouper Epinephelus marginatus
No full textEpinephelus marginatus is a monandric protogynous hermaphrodite in which sex change mainly occurs in individuals 14-17 years old or 80-90 cm long. This sexual pattern arises several problems for broodstock management and artificial propagation. Our study aimed at identifying precocious sex inversion techniques for aquaculture practices. Sex inversion was induced in wild juveniles (mean body weight 1.6 Kg, BW) both by oral and intramuscular administration of 17-methyltestosterone (MT). Eighteen fish, kept in PVC tanks isolated or grouped, received MT at 1-mg/Kg BW using different feeding methods. Eight fish were treated by MT injection at 2-mg/Kg BW dosage, every 7-10 days. Four fish were used as controls. Milt was evaluated for volume, sperm density, vitality and motility. Histological analyses of gonads were carried out at the beginning and at the end of the trials both in successful and unsuccessful sex-inverted fish. Sex inversion from immature females to spermiating males was observed in 3 of 8 MT injected fish (mean accumulated dose of 30.6mg/Kg BW) after 16 weeks. MT oral administration was successful in 13 of 18 treated fish after 14-18 weeks (mean MT accumulated dose of 66.4 mg/Kg BW, range 36.8-92.1 mg/Kg BW). Spermiating fish produced 10-100 l of milt. Sperm density ranged between 14 x106 and 7.7x109 cell/ml. Milt from sex inverted fish was effective in egg fertilisation (62%). Histologically, after sex change ovary was completely replaced by male tissue with cysts of germ cells at different stages. Free spermatozoa filled the spermatic ducts. RIAs of 17ß-estradiol (17ß-E), testosterone (T), 11-ketotestosterone (11-KT) and 11ß-hydroxyandrostenedione (11ß-OHA) are in progress to identify key-sex steroids involved in sex change
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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