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  • 1
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Aquaculture research 18 (1987), S. 0 
    ISSN: 1365-2109
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract. As currently practiced, freshwater prawn, Macrobrachium rosenbergii (de Man), aquaculture in Hawaii requires large inputs of supplementary feed, water and labour. The high cost of these inputs greatly restricts profit potential. An experiment was conducted to compare an alternative prawn production system which used lower feeding rates and fish polycultures to reduce inputs. Three treatments were run in quadruplicate: (1) control—prawns stocked at standard densities (11.5 per n2) in monoculture and fed standard prawn pellets at the commercial ration recommendations by New & Singholka (1982); (2) low feed—prawns at standard densities and fish [silver carp, Hypophthalmichthys molitrix (Valenciennes), grass carp, Ctenopharyngodon idella (Valenciennes), and grey mullet, Mugil cephalus (L.)] fed one-half commercial ration; and (3) maintenance feed—prawns at standard densities and fish fed one-tenth commercial ration. Although prawn yield characteristics (mean weights, harvestable sizes, survival, net yields) were not significantly different (P 〉 0.05) based on an analysis of variance in the three treatments over the approximately 9.5-month culture period, this lack of significance most likely resulted from interpond variability and the lack of a large number of replicates. The relatively poor survival (60–63%) of gray mullet and an almost twofold difference in prawn yields in the control and maintenance feed treatments suggest that there was in fact competition for resources in the nominally polyculture systems. Nevertheless, the wet weight yield of biomass from all species was twice as high in the low feed ponds as in the control ponds.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 85 (1971), S. 0 
    ISSN: 1365-2133
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Summary.— Several commercially available topical corticosteroid products have been evaluated in the blanching test. Fluocinolone acetonide preparations are extremely effective, and the ointment is superior to the other ointment products. Fluocinolone acetonide cream and gel produce a more prolonged effect than other cream products.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    British journal of dermatology 85 (1971), S. 0 
    ISSN: 1365-2133
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Summary.— “Metosyn”,* a new eorticosteroid in a novel topieal formulation, has been examined in the blanehing test and has been found to be a highly effective preparation, surpassing even the high responses of betamethasone valerate cream and ointment.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Marine biology 62 (1981), S. 73-79 
    ISSN: 1432-1793
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A new method is described for the determination of phytoplankton growth rates and carbon biomass. This procedure is easy to apply and utilizes the labeling of chlorophyll a (chl a) with 14C. Pure chl a is isolated using two-way thin-layer chromatography, and the specific activity of chl a carbon is determined. Data from laboratory cultures indicate that the specific activity of chl a carbon becomes nearly equal to that of total phytoplankton carbon in incubations lasting 6 to 12 h and can be used to calculate phytoplankton growth rates and carbon biomass. Application of the method to the phytoplankton community in an eutrophic estuary in Hawaii indicates that the cells are growing with a doubling time of about 2 d and that about 85% of the particulate carbon consists of phytoplankton carbon.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Marine biology 65 (1981), S. 13-16 
    ISSN: 1432-1793
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The Model I linear regression theory is often used in the analysis of data under conditions when the Model II theory is clearly needed. Implications derived from the use of the two theories can differ greatly when there is not a high degree of correlation between the X and Y variables. The geometric mean Model II method is easy to use, and is probably needed in the analysis of most field data, since the X variable in field data is rarely under the control of the investigator.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 25 (1983), S. 2319-2335 
    ISSN: 0006-3592
    Schlagwort(e): Chemistry ; Biochemistry and Biotechnology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Arrays of foils similar in design to airplane wings have been placed in an algal culture flume to create systematic mixing. Vortices are produced in the culture due to the pressure differential created as water flows over and under the foils. In a flume having a flow rate of 30 cm/s, the foil arrays produced vortices with rotation rates of ca. 0.5-1.0 Hz. This rotation rate is satisfactory to take advantage of the flashing light effect if the culture is sufficiently dense. Solar energy conversion efficiencies in an experimental culture of P. tricornutum increased 2.2-2.4 fold with the foil arrays in place versus controls with no foil arrays and solar energy conversion efficiencies averaged 3.7% over a three-month period. Five-day running means of solar energy conversion efficiencies reached as high as 10% during the three-month period. The use of foil arrays appears to be an effective and inexpensive way to utilize the flashing light effect in a dense algal culture system.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 28 (1986), S. 191-197 
    ISSN: 0006-3592
    Schlagwort(e): Chemistry ; Biochemistry and Biotechnology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: A mass culture of Tetraselmis suecica grown in seawater enriched with only inorganic nutrients and CO2 in a shallow outdoor flume containing foil arrays to effect systematic vertical mixing achieved average daily production rates of over 40 g ash-free dry wt (AFDW)/m2 over periods as long as one month when grown on a three-day dilution cycle. Photosynthetic efficiencies associated with these high production rates averaged 8-11% based on visible irradiance. Operation of the system in a one-, two-, or four-day dilution cycle resulted in lower photosynthetic efficiencies of 6-7%. A remarkable feature of the three-day dilution cycle results was the fact that production on the third day after dilution averaged 60-70 g AFDW/m2, and corresponding photosynthetic efficiencies averaged 13-19%. The high production rates and photosynthetic efficiencies achieved on the third day after dilution may have reflected the nonequilibrium nature of the production cycle and, in particular, the fact that the adaptation of the cells to changing light condition lagged behind light condition in the culture.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 8
    Publikationsdatum: 2016-09-07
    Beschreibung: Oceanic ecosystems altered by interdecadal climate variability may provide a feedback to the physical climate by phytoplankton affecting heat fluxes into the upper ocean and dimethylsulfide fluxes into the atmosphere
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 9
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geochemistry, Geophysics, Geosystems, 2 (2000GC000057).
    Publikationsdatum: 2018-01-30
    Beschreibung: [1] Although the biochemical functions and biosynthetic pathways of alkenones are still largely unknown, alkenone unsaturation ratios are now used extensively to infer ancient sea surface temperature, and their isotopic compositions have been used to reconstruct ancient atmospheric CO2 levels. The inferred relationships between alkenone unsaturation ratios, isotopic compositions, and growth conditions are based on empirical laboratory and field studies and, in the case of isotope fractionation, on simple models of carbon acquisition and fixation. Significant uncertainty still exists concerning the physiological and ecological factors affecting cellular production of alkenones, unsaturation ratios, and isotopic composition. Phytoplankton culture conditions have been shown to affect alkenone unsaturation (U37K′), cellular alkenone content, intracellular isotopic compositions (Δδ), and changes in fractionation (εP) as a function of the quotient of algal growth rate and aqueous carbon dioxide concentration (μ/CO2). Such studies imply that plant physiology can affect the interpretation of environmental signals. The factor(s) controlling cellular alkenone concentrations and unsaturation ratios are reviewed, as well as the carbon isotopic composition of the alkenone-producing algae. A new technique is presented to determine growth rates of the alkenone-containing algae in natural settings that will facilitate testing laboratory-based hypotheses concerning the carbon isotopic fractionation and its relationship to growth rate/growth status of alkenone-producing algae in the field.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 10
    facet.materialart.
    Unbekannt
    AGU (American Geophysical Union)
    In:  Geochemistry, Geophysics, Geosystems, 2 .
    Publikationsdatum: 2018-01-30
    Beschreibung: The number of double bonds in long-chain, unsaturated ketones (alkenones) produced by some members of the Haptophyceae is correlated with the ambient temperature at the time of synthesis. For these same organisms the depletion of carbon-13 in biosynthetic products relative to dissolved inorganic carbon is related directly to the specific growth rate and inversely to the concentration of dissolved carbon dioxide. This report summarizes issues relating to the physiology, metabolism, and biochemistry of alkenone producers and how they affect the abundances and isotopic compositions of alkenones. These considerations show that an understanding of cellular responses to parameters governing uptake of inorganic carbon (Ci), isotopic fractionation, growth under diverse nutrient conditions, and genetic variability, both in the field and in culture, is necessary for developing a conceptual understanding of the biological significance of the ɛP and U37K′ indices. Emiliana huxleyi is the best known alkenone producer and can serve as a model organism for these studies. This report identifies knowledge gaps and appropriate objectives for both field- and laboratory-based research.
    Materialart: Article , PeerReviewed
    Format: text
    Standort Signatur Einschränkungen Verfügbarkeit
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