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  • 1
    ISSN: 1573-5117
    Keywords: fish ; assemblage ; artificial reefs ; substrate ; colonization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Migjorn artificial reef (MAR) was deployed in the summer of 1990 and is made by 48 concrete blocks set 30 m deep on a sea bed of sand with a small proportion of Posidonia oceanica (L.) Delile meadow. Visual censuses of blocks on both substrata were carried out during the months of February, May and September in 1992 and 1993. The MAR fish assemblages were influenced by the surronding substrate. Thus, a group of ubiquitous species, frequent on both substrata and typical of natural rocky habitats (mostly Sparidae) and a group associated with the samples recorded on the Posidonia meadow (mostly Labridae) could be distinguished. Season had only a secondary and slight effect on fish assemblages. The MAR was colonized by 74% of the species in the first two years after deployment. Positive and lineal relationships between species richness, diversity, abundance of necto-benthic species and time since deployment on sandy substrata were found. On Posidonia oceanica deployment time has only increased very sedentary and cryptic species. Although some ways in which the MAR would have a productive function are not rejected, the most obvious MAR working pattern is that of fish aggregation.
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  • 2
    ISSN: 1573-5117
    Keywords: fish ; assemblage ; artificial reefs ; substrate ; colonization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The Migjorn artificial reef (MAR) was deployed in the summer of 1990 and is made by 48 concrete blocks set 30 m deep on a sea bed of sand with a small proportion of Posidonia oceanica (L.) Delile meadow. Visual censuses of blocks on both substrata were carried out during the months of February, May and September in 1992 and 1993. The MAR fish assemblages were influenced by the surronding substrate. Thus, a group of ubiquitous species, frequent on both substrata and typical of natural rocky habitats (mostly Sparidae) and a group associated with the samples recorded on the Posidonia meadow (mostly Labridae) could be distinguished. Season had only a secondary and slight effect on fish assemblages. The MAR was colonized by 74% of the species in the first two years after deployment. Positive and lineal relationships between species richness, diversity, abundance of necto-benthic species and time since deployment on sandy substrata were found. On Posidonia oceanica deployment time has only increased very sedentary and cryptic species. Although some ways in which the MAR would have a productive function are not rejected, the most obvious MAR working pattern is that of fish aggregation.
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  • 3
    ISSN: 1570-7458
    Keywords: Ajuga reptans ; Trialeurodes vaporariorum ; bioassay ; phytoecdysteroids ; larval mortality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A rapid and reliable in vitro bioassay method to test the effects of synthetic and natural compounds on the development of greenhouse whitefly Trialeurodes vaporariorum Westwood (Homoptera Aleyrodidae) is described. Leaf fragments of Nicotiana glauca Graham infested with eggs of whitefly were cultured under aseptic conditions on half-strength Murashige-Skoog medium. The development of the insect in vitro and in vivo were comparable except for a higher mortality rate in the first larval instar. Ecdysteroids from Ajuga reptans L. were applied to leaf fragments by immersion in aqueous solution of the compounds or by addition to the culture medium. A high mortality rate of first larval instars was detected with 29-norsengosterone and ajugalactone treatments. This effect was specially pronounced when the products were incorporated in the medium. A significant increase in mortality was also recorded in the pupal state with a 20-hydroxyecdysone treatment. This effect was never observed before, because all whitefly larvae on A. reptans leaves die in the first larval instar.
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  • 4
    ISSN: 1573-1561
    Keywords: Sinularia spp. ; spawning ; soft coral ; pukalide ; epoxypukalide ; structure determination ; diterpene ; octocorals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Chemical analysis of the eggs spawned by fiveSinularia soft corals (Octocorallia, Alcyoniidae) collected in the central region of the Great Barrier Reef, Australia, revealed the presence of the known cembranoid diterpenes epoxypukalide and/or pukalide in all cases. Examination of the colonies from which the eggs were released one month before spawning and also some time after spawning failed to detect either diterpene in the coral tissue. The three dimensional structures of pukalide and epoxypukalide, as determined by the single-crystal X-ray technique, are reported for the first time. The wide distribution of pukalide and epoxypukalide and of related compounds within the octocorallia is discussed.
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  • 5
    ISSN: 1573-1561
    Keywords: Allelopathy ; diterpenes ; soft corals ; Sinularia flexibilis ; Coelenterata ; Octocorallia ; variability ; competition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Colonies of the soft coralSinularia flexibilis (Quoy & Gaimard) (Coelenterata, Octocorallia) were collected at Lizard Island (14°40′S and 145°28′E) Research Station. Extraction of the corals and quantitative chemical analysis for the three major diterpene components, flexibilide, dihydroflexibilide, and sinulariolide, afforded average ratios of 4∶3∶1 respectively. Colonies, sized on the basis of the sterile stalk circumference, were analyzed for possible correlations between size and chemical composition. The major metabolite, flexibilide, was inversely correlated with colony size, while sinulariolide concentration showed a direct correlation. The concentration of dihydroflexibilide was independent of colony size. Samples were further analyzed with respect to site of collection. Colonies were collected at three distinct reefal sites. One was characterized by large monospecific stands ofParites cylindrica, a second was a sandy bottom site with a mixed community of soft corals and occasional scleractinians, while the third site was a very diverse reef community with many species of scleractinian corals.Sinularia flexibilis was well represented at each site, and the concentration of flexibilide and sinulariolide varied significantly among sites. The concentration of flexibilide was significantly higher at the third, highly competitive site, while the concentration of sinulariolide was highest at thePorites-dominated site. Dihydroflexibilide levels were independent of site. It seems likely that concentrations of flexibilide, a highly cytotoxic molecule involved in interference competition, and sinulariolide, a known algicide probably responsible for colony maintenance, may be influenced by their environments.
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  • 6
    ISSN: 1573-1561
    Keywords: Key Words ; Vomiting ; emesis ; terpenoid ; cembranoid ; octocoral ; pukalide ; fish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Tissue and extractable metabolites from the subtropical gorgonianLeptogorgia virgulata (Coelenterata: Anthozoa: Octocorallia: Gorgonacea) induce vomiting in a variety of fish species. To elucidate the chemical bases of this phenomenon, experiments were undertaken with purified pukalide, a cembranoid diterpene that comprises as much as 0.1–0.5% of the wet tissue weight ofL. virgulata. When incorporated into artificial foods at concentrations corresponding to the levels found inL. virgulata, pukalide induced emesis when delivered orally to killifish (Fundulus heteroclitus). The threshold dose for pukalide-induced emesis was 0.05 mg/g fish body weight. Control pellets devoid of pukalide did not induce vomiting. The emetic effect of pukalide was dose-dependent, as fish ingesting more than 0.100 mg pukalide/ g body weight exhibited a significantly higher incidence of vomiting than fish ingesting lower doses of pukalide (G=5.5,df=1,P〈0.025). The elapsed time between ingestion of pukalide-containing pellets and emesis was significantly longer in fish that ingested marginally emetic doses of pukalide (Kruskal-WallisH=4.00, significant withP〈0.05). Although not markedly unpalatable to fish, pukalide may function in nature as a defensive toxin by inducing emesis and learned aversion in potential octocoral predators.
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  • 7
    ISSN: 1573-7284
    Keywords: Measles ; Seroepidemiology ; Vaccination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A seroepidemiological study of measles immunological status was carried out among four different populations: schoolchildren of 6–7 years, 10–11 years and 13–14 years, and pregnant women of 18–45 years, in Catalonia, Spain; 1,213 children and 239 pregnant women were surveyed. The measurement of measles antibodies was made by indirect immunofluorescence, with antibody titres ≥ 1:8 considered as positive. The prevalence of measles antibodies was 82.9% in the 6–7 year old group, 87.2%, in the 10–11 year old group and 94.4% in the age group 13–14 years. Among pregnant women, the prevalence of antibodies was 96.2%. Two of the variables studied were associated with the prevalence of measles antibodies in schoolchildren: the disease antecedents and measles vaccination. In pregnant women aged 18–45 no variable had any stastically significant association with the prevalence of measles antibodies.
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  • 8
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 4 (1970), S. 373-382 
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The mass spectra of twenty-seven C-19 modified cholestane derivatives have been determined, and have been compared with the mass spectra of similar compounds reported1 in the cholesteryl series. In the spectra of 2α,19-dihydroxy-5α-cholestane (la), initial loss of the 10β-hydroxymethyl group was observed followed by loss of water, whereas with the 2α-methoxy and 2α-acetoxy derivatives (Ib, Ic), loss of the 2α-substituent as methanol and acetic acid respectively, preceded the elimination of the 10β-hydroxymethyl group. Loss of the 10β-hydroxymethyl group was also observed in Δ1-, Δ2- and 2-oxo derivatives (VI, Va and VII), whilst loss of both the 1 substituent and the 10β-hydroxymethyl group from the molecular ion was observed with the 1α-ol (IIa) and the 1β-yl-chloride (III).In a series of 19-acetoxy derivatives loss of acetic acid [M - 60] from the 19-acetoxy group, involving abstraction of a sterically favourable hydrogen, always occurred, although this was usually accompanied by loss of the 10β-acetoxymethyl residue [M - 73].The mass spectra of a series of 10β-carboxylic acids and their methyl esters were more complex with three or more fragmentation patterns being observed. 1,3-Diaxial interactions, similar to those observed in chemical reactions, were observed in the mass spectra of three 2β-oxygenated-19-substituted compounds.
    Additional Material: 6 Ill.
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  • 9
    ISSN: 1439-0973
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei AIDS-Patienten sind zahlreiche Manifestationsformen der extrapulmonalen Tuberkulose bekannt; eine Perikardbeteiligung wurde jedoch nur selten beschrieben. Wir berichten über einen Fall von tuberkulöser Perikarditis bei einem AIDS-Patienten mit gutem Ansprechen auf die antituberkulöse Therapie. Trotz der Seltenheit einer tuberkulösen Perikarditis bei Patienten mit symptomatischer HIV-Infektion sollte wegen der günstigen Behandlungsmöglichkeiten bei Verdacht eine aggressive Diagnostik durchgeführt werden.
    Notes: Summary Although it is known that extrapulmonary tuberculosis in patients with AIDS has a broad spectrum of clinical manifestations, pericardial involvement has rarely been described. We report a case of this condition as the first manifestation of AIDS with good response to antituberculous therapy. Although unusual, the diagnosis of tuberculous pericarditis in symptomatic HIV-infected patients should be aggressively pursued because of the beneficial clinical response to treatment.
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  • 10
    ISSN: 1572-8854
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The crystal structure of the title compound has been determined. The crystals are orthorhombic:Pbnb, (bca setting of Pccn, No 56),a=18.053(8),b=15.532(4),c=16.915(6) Å,V c =4743(3) Å3,Z=8,D x =1.17 Mg m−3,λ=(MoKα)=0.71069 Å. The structure was solved by direct methods and refined with 1352 reflections to a finalR value of 0.067. Mass and spectral data (IR, UV,1H and13C NMR) are also reported.
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