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  • Acceptability  (1)
  • Anguilla dieffenbachii  (1)
  • Asymptotic approximations  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Gonad histology and plasma steroid profiles in wild New Zealand freshwater eels (Anguilla dieffenbachii and A. australis) before and at the onset of the natural spawning migration. II. Males (1998)
    Springer
    Fish physiology and biochemistry 19 (1998), S. 339-347 
    Details
    ISSN: 1573-5168
    Keywords: spawning migration ; spermatogenesis ; freshwater eels (Teleostei) ; Anguilla dieffenbachii ; Anguilla australis ; male ; histology ; steroid profiles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Immature and maturing male New Zealand freshwater eels, the shortfinned Anguilla australis and the longfinned A. dieffenbachii, were caught from the wild to obtain data on the natural reproductive physiology of these fish. Plasma samples were analysed for steroid hormones by radioimmunoassay and values related to the developmental stage of the testes. Our histological observations on testes largely confirmed those reported previously. Thus, the gonad of non-migrating eels often appeared undifferentiated or poorly developed, containing only type A or early type B spermatogonia. In contrast, the testes of migrating shortfins were in early spermatogenesis as evidenced by the presence of late type B spermatogonia. Similarly, early spermatogenic stages were common in migratory longfins, but eels in midspermatogenesis (all germ cell stages present) were also encountered. Unlike a previous study, patches of testicular regression were commonly seen in migrants of both species. Levels of several androgens, androstenedione (AD), testosterone and 11-ketotestosterone (KT), were elevated in migrants compared to non-migrants. AD was higher in early to midspermatogenic A. dieffenbachii (0.63 ng ml−1) than in A. australis (0.25 ng ml−1) in the spermatogonial proliferation stage, while the inverse was observed for KT (27.78 ng ml−1 and 50.52 ng ml−1, respectively). Levels of 17,20β-dihydroxy-4-pregnen-3-one were nearly undetectable (less than 0.12 ng ml−1) in all animals. Plasma 17-hydroxyprogesterone concentrations in fyke-caught eels were elevated to a greater extent in non-migrants (up to 1.92 ng ml−1) than in migrants (around 0.5 ng ml−1), and correlated well with levels of cortisol in all groups. Histological results are compared to previous studies and the presence of regression in the testes is discussed. In addition, the role of steroid hormones, in particular AD and KT, in reproduction and stress is considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007767330225
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Analytical approximations for iterated bootstrap confidence intervals (1992)
    Springer
    Statistics and computing 2 (1992), S. 161-171 
    Details
    ISSN: 1573-1375
    Keywords: Asymptotic approximations ; bootstrap calibration ; coverage accuracy ; resampling ; saddlepoint methods ; tail probability approximations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract Standard algorithms for the construction of iterated bootstrap confidence intervals are computationally very demanding, requiring nested levels of bootstrap resampling. We propose an alternative approach to constructing double bootstrap confidence intervals that involves replacing the inner level of resampling by an analytical approximation. This approximation is based on saddlepoint methods and a tail probability approximation of DiCiccio and Martin (1991). Our technique significantly reduces the computational expense of iterated bootstrap calculations. A formal algorithm for the construction of our approximate iterated bootstrap confidence intervals is presented, and some crucial practical issues arising in its implementation are discussed. Our procedure is illustrated in the case of constructing confidence intervals for ratios of means using both real and simulated data. We repeat an experiment of Schenker (1985) involving the construction of bootstrap confidence intervals for a variance and demonstrate that our technique makes feasible the construction of accurate bootstrap confidence intervals in that context. Finally, we investigate the use of our technique in a more complex setting, that of constructing confidence intervals for a correlation coefficient.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01891208
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Acceptability of green soybeans as a vegetable entity (2000)
    Springer
    Plant foods for human nutrition 55 (2000), S. 323-333 
    Details
    ISSN: 1573-9104
    Keywords: Acceptability ; Evaluation ; Genotypes ; Panel ; Sensory ; Soybean (Glycine max [L.] Merr.) ; Vegetable
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A profile of the sensory characteristics of greensoybean and consumer intent of purchasing the productwere determined. Thirty-one green soybean genotypesfrom maturity groups III to VI harvested between R6and R7 were frozen, boiled, shelled, and evaluated forcolor, texture, sweetness, nuttiness, beaniness,oiliness, aftertaste and overall eating quality bythree sensory panels. Results showed highly significant (p〈0.01) variabilities among the genotypes in allsensory parameters and highly significant correlationsamong several parameters. The green soybeans, whenboiled, ranged from lightly green to green, wereslightly resistant to chewing, slightly nutty,slightly beany, not oily, imparted a pleasantaftertaste and had a fairly good overall eatingquality. The green soybeans would be potentiallyacceptable as a vegetable in the frozen state and foruse in recipes. When selecting genotypes forproduction, consideration should be given to thesensory attributes of the genotypes, because there wassignificant variability among the characteristics ofthe green soybeans, and several characteristicstogether enhanced the overall acceptability of thevegetable soybeans. To further increase theacceptability of green soybeans as a vegetable,geneticists need to consider breeding a vegetablesoybean that has as many desirable sensory attributesas possible.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008164925103
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    Paper (German National Licenses)
    Fulltext
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