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31.
Six additional characters are proposed to distinguish the nymphs of the perlid genera from Southeastern Brazil, and a practical key is provided. 相似文献
32.
《Archives of animal nutrition》2013,67(5):373-382
A review of past literature revealed inconsistencies in recommended feed particle size for optimal growth and productive performance of rabbits. Changing diet formulation and subsequent processing conditions may improve pellet texture and potentially affect rabbit performance. In the current study, two isoenergetic and isonitrogenous pelleted diets were formulated, which varied in the particle size of the concentrates (2 and 8 mm, respectively). The objective was to evaluate the effect of different particle sizes of compound diets on performance, nutrient utilisation, gut morphology, and carcass characteristics of fattening Italian White breed rabbits. The finely ground diet led to a significant improvement in feed efficiency and apparent digestibility of crude protein, ether extract, crude fibre and NDF, without any negative effect on gut morphology. Furthermore, a smaller particle size of concentrates in pelleted diets improved carcass traits. Meat colour parameters showed significant differences in longissimus lumborum and biceps femoris due to dietary treatments, but in both muscles pH values 1 h and 24 h after slaughter remained unchanged. It is concluded that a finely ground pelleted diet can be used to improve growth performance of rabbits without affecting carcass parameters. 相似文献
33.
Masaru Manabe Tetsuhisa Goto Shinji Matsuura 《Bioscience, biotechnology, and biochemistry》2013,77(11):2003-2007
Aflatoxins Bl, B2, G1 and G2 were quantitatively detected by high-performance liquid chromatography on a 12 µl flow-cell in the fluorometric detector using the mobile phase of toluene system instead of chloroform, dichloromethane or methanol system. Various kinds of columns and mobile phases were tested, and fine mutual separation of all the four aflatoxins without quenching their fluorescence was achieved by using sHica gel column and toluene- ethyl acetate-formic acid-methanol (89.0: 7.5: 2.0: 1.5 v/v/v/v). The relationship between the fluorescence peak area and the amount injected was linear in the range of 0.3 ng to 120 ng. This method, as applied to food and feed extracts, is sensitive at the 10~20 ppb levels of the four kinds of aflatoxins. 相似文献
34.
Katsumi Kakinuma Noboru Ōtake Hiroshi Yonehara 《Bioscience, biotechnology, and biochemistry》2013,77(12):2529-2538
The structure of detoxin D1, one of the main active principles of detoxio complex, has been established on the basis of the degradative studies and spectral evidences as depicted in formula (I).Detoxin D1 has been demonstrated to belong to a new class of the depsipeptide contained an amino acid designated detoxinine which was newly isolated as a natural product. 相似文献
35.
The cicada genus Nipponosemia Kato is reviewed. Four species are illustrated, photographed and described, including three known species and one new species. A key to all species of this genusis presented, and information on the biology of Nipponosemia are provided. The systematic status of the tribe Cicadatrini and biogeography of Nipponosemia are discussed. 相似文献
36.
《Plant Ecology & Diversity》2013,6(3-4):495-501
Background: The adaptation, evolution and function of flower colour diversity in response to changing environments are one of the oldest puzzles in plant ecology. It is logical that comparative studies on fitness of flower colour would be the most meaningful if they were conducted on the same genotype. Aims: We used Gentiana leucomelaena, which produces both white and blue flowers on different tillers of the same individual, as a model species to test adaption and fitness differences of contrasting flowers in contrasting environments. Methods: We examined seed production by white and blue flowers in response to increased temperatures (28 °C/2 °C vs. 12 °C/2 °C; 12 h light/12 h dark) in a climate chamber study and to watering in the field (+1.5 l m?2 d?1 vs. control with no supplementary irrigation). Results: For white and blue flowers warming decreased but watering increased seed number. Increased temperature and watering increased the size of seeds from white flowers, but neither warming nor watering significantly changed seed size of blue flowers. Seed size was significantly negatively correlated with seed number in the temperature treatments but positively correlated in watering treatments. The positive correlation was strong in white flowers, but the negative correlation was stronger in blue than in white flowers. Conclusions: Water availability and low temperature confer an advantage to white flowers, while warming and dry habitats favour blue flowers. These divergent responses may influence total plant fitness and thus help explain the adaptive value and evolution of flower colour diversity. 相似文献
37.
JEAN-YVES DUBUISSON 《Botanical journal of the Linnean Society. Linnean Society of London》1997,123(4):265-296
Systematics within the genus Trichomanes sensu lato (Hymenophyllaceae, Filicopsida) have continued to be controversial because of the difficulty in identifying homologies and informative characters within high morphological diversity. Systematic relationships are investigated in this study by using a cladistic approach with 31 anatomical and morphological characters from 20 taxa which correspond to the sections defined by Morton. The results broadly confirm Morton's four subgenera: Trichomanes, Didymoglossum, Pachychaetum and Achomanes. The monophyly of Pachychaetum remains fragile and the section Lacostea appears to be excluded from its traditional subgenus (Achomanes). In addition, by producing two major 'ecological' clades (terrestrial and epiphytic), the analysis shows that several selected characters appear to be strongly linked with the ecology which may have a significant influence on the topology. 相似文献
38.
39.
Precise cellular localization of the GUS stain is notoriously difficult inArabidopsis seeds. Here we report an improved protocol for the clearing of seeds after GUS staining. Incubation in ethanol-acetic acid
(EtAc) and Hoyer’s medium allows reliable cellular localization of the GUS, even in seeds from late developmental stages.
This method also leads to the staining of nucleoli in the endosperm and embryo, facilitating nuclear counts in endosperm development.
An erratum to this article is available at . 相似文献
40.
Gerd Gäde 《Physiological Entomology》2002,27(1):51-57
Abstract In the field, adult males of the grasshopper Phymateus morbillosus are able to fly for up to 1 min and cover up to c. 100 m, whereas females, although fully winged, are apparently unable to get airborne. Morphometric data indicate that the males are lighter, have longer wings, a higher ratio of flight muscles to body mass, and a lower wing load value than females. It was investigated whether this inability of females to fly is related to fuel storage, flight muscle enzymatic design and/or the presence and quantitative capacity of the endocrine system to mobilize fuels. In both sexes, readily available potential energy substrates are present in the haemolymph in similar concentrations, and the amount of glycogen in flight muscles and fat bodies does not differ significantly between males and females. Mass-specific activities of the enzymes GAPDH (glycolysis), HOAD (fatty acid oxidation) and MDH (citric acid cycle) in flight muscles are significantly lower in females compared with males, and mitochondria are less abundant in the flight muscles of females. There is no significant difference between the ability of the two sexes to oxidize various important substrates. Both sexes contain three adipokinetic peptides in their corpora cardiaca; the amount of each peptide in female grasshoppers is higher than in males.
Thus, despite some differences listed above, both sexes appear to have sufficient substrates and the necessary endocrine complement to engage in flight. It seems more likely, from the morphometric data above, that the chief reason for flightlessness is that P. morbillosus females cannot produce sufficient lift for flight; alternatively, the neuronal functioning associated with the flight muscles may be impaired in females. 相似文献
Thus, despite some differences listed above, both sexes appear to have sufficient substrates and the necessary endocrine complement to engage in flight. It seems more likely, from the morphometric data above, that the chief reason for flightlessness is that P. morbillosus females cannot produce sufficient lift for flight; alternatively, the neuronal functioning associated with the flight muscles may be impaired in females. 相似文献