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1.
Energy storage in arthropods has important implications for survival and reproduction. The lipid content of 276 species of adult arthropods with wet mass in the range 0.2–6.13 g is determined to assess how lipid mass scales with body mass. The relative contribution of lipids to total body mass is investigated with respect to phylogeny, ontogeny and sex. The lipid content of adult insects, arachnids, and arthropods in general shows an isometric scaling relationship with respect to body mass (M) (Marthropod lipid = ?1.09 ×Mdry1.01 and Marthropod lipid = ?1.00 ×Mlean0.98). However, lipid allocation varies between arthropod taxa, as well as with sex and developmental stage within arthropod taxa. Female insects and arachnids generally have higher lipid contents than males, and larval holometabolous insects and juvenile arachnids have higher lipid contents than adults. 相似文献
2.
Andreas Barth 《BBA》2007,1767(9):1073-1101
This review discusses the application of infrared spectroscopy to the study of proteins. The focus is on the mid-infrared spectral region and the study of protein reactions by reaction-induced infrared difference spectroscopy. 相似文献
3.
《Bioscience, biotechnology, and biochemistry》2013,77(4):567-571
Casein was conjugated with dextran and galactomannan in a controlled dry state at a relative humidity of 79% and at 60°C for 24 hr. The covalent attachment of polysaccharides to casein was confirmed by SDS-PAGE and HPLC. The emulsifying activity of the casein-dextran and casein-galactomannan conjugates was 1.5 times higher than that of casein. The emulsion stability of the casein-dextran and casein-galactomannan conjugates was 10 times higher than that of casein. The improvement in these emulsifying properties reached a steady state when the conjugation of casein with polysaccharide was done for 24 hr in a controlled dry state, suggesting the rapid formation of conjugates through a Maillard reaction in the case of casein. Compared to commercial emulsifiers, the casein-polysaccharide conjugates showed better emulsifying properties in acidic and high-salt concentration systems. 相似文献
4.
Scaling of metabolic rate with body mass and temperature in teleost fish 总被引:27,自引:0,他引:27
5.
J. N. Sachan Basudeo Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(4):571-574
Summary Components of generation means were partitioned for days to flower initiation and maturity in three crosses of Indian mustard (Brassica juncea (L.) Czern and Coss) cultivars. A linked digenics model was adequate for flowering in cross II and maturity in Cross I. All three types of digenic interactions among the linked pairs of genes, additive X additive (i), additive X dominance (j) and dominance X dominance (1), contributed significantly in the inheritance of flowering in cross II and maturity in cross I. A complete association among the genes of greater effects in higher mean parent was detected for flowering in cross II and maturity in Cross I. Duplicate epistasis was evident for flowering in Crosses I and II and maturity in Crosses I and III.Inadequacy of all the fitted models for days to flowering in Cross III and maturity in Cross II indicated the presence of higher order interactions.Part of PhD (plant breeding) Thesis, submitted by senior author to GBPUAT, Pantnagar (Nainital) U.P., India (unpublished). Research paper No. 4262 相似文献
6.
B. Sinha R. M. Singh U. P. Singh 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,82(4):399-404
Summary Studies on the genetics of leaf blight caused byAlternaria triticina using generation mean analysis revealed that additive components played a major role, but that dominance components also contributed significantly in controlling the variability for leaf blight resistance in wheat crosses. Furthermore, the additive x additive type of epistasis was predominant in the first three crosses, whereas in the fourth cross additive x dominance (j) and dominance x dominance (1) components of epistasis were most significant. Because of this it may be desirable to follow a simple recurrent selection scheme for higher tolerance, to isolate resistant plants from the segregating populations derived from crosses of parents of diverse origin following the pedigree method of breeding. CPAN-1887 was very tolerant to leaf blight in the present study and should be utilized in hybridization programs to develop leaf-blight-resistant varieties. 相似文献
7.
The purpose of this study was to determine if selected biochemical parameters representing the contractile and calcium regulating systems of cardiac muscle scaled among mammals having inherently different resting heart rates (RHR). Eight mammalian species with RHR ranging from 51 to 475 beats per minute (bpm) were studied.The oxidative capacity of the myocardium is highly correlated with the RHR. The hypothesis of the present study was that the capacities of the energy utilizing processes of contraction and calcium regulation would also be correlated to the functional demand imposed on the muscle as represented by the RHR.Myosin (M) and myofibrillar (MF) ATPase activities, myosin isoenzyme distribution and sarcoplasmic reticulum (SR) ATPase activity were determined. Animals with RHR above 300 bpm express V1 myosin while animals with lower RHR express primarily V3. M and MF ATPase activities correlated with RHR, but the major difference in activities occurred at the threshold RHR of about 300 bpm at which the switch from V3 to V1 appears to occur. SR ATPase activity per mg of microsomal protein was for the most part constant among different mammals, but the SR ATPase activity per g of heart tissue was significantly correlated with RHR as slower beating hearts tended to yield less SR protein per unit mass.We conclude that both the contractile and calcium regulating systems are scaled to the functional parameter of RHR among different mammals. The contractile system uses a slow myosin ATPase isoform at low resting heart rates whereas above the postulated threshold RHR of about 300 bpm a switch in gene expression to a fast myosin ATPase isoform occurs. For the calcium regulating system, the heart does not seem to have the choice of altering the quality of the SR ATPase isoform and thus calcium regulating capacity is set by alterations in the quantity of SR per unit of heart mass. 相似文献
8.
Understanding WaveShrink: Variance and bias estimation 总被引:15,自引:0,他引:15
9.
10.
J M Cheverud L A Kohn L W Konigsberg S R Leigh 《American journal of physical anthropology》1992,88(3):323-345
Artificial reshaping of the cranial vault has been practiced by many human groups and provides a natural experiment in which the relationships of neurocranial, cranial base, and facial growth can be investigated. We test the hypothesis that fronto-occipital artificial reshaping of the neurocranial vault results in specific changes in the cranial base and face. Fronto-occipital reshaping results from the application of pads or a cradle board which constrains cranial vault growth, limiting growth between the frontal and occipital and allowing compensatory growth of the parietals in a mediolateral direction. Two skeletal series including both normal and artificially modified crania are analyzed, a prehistoric Peruvian Ancon sample (47 normal, 64 modified crania) and a Songish Indian sample from British Columbia (6 normal, 4 modified). Three-dimensional coordinates of 53 landmarks were measured with a diagraph and used to form 9 finite elements as a prelude to finite element scaling analysis. Finite element scaling was used to compare average normal and modified crania and the results were evaluated for statistical significance using a bootstrap test. Fronto-occipitally reshaped Ancon crania are significantly different from normal in the vault, cranial base, and face. The vault is compressed along an anterior-superior to posterior-inferior axis and expanded along a mediolateral axis in modified individuals. The cranial base is wider and shallower in the modified crania and the face is foreshortened and wider with the anterior orbital rim moving inferior and posterior towards the cranial base. The Songish crania display a different modification of the vault and face, indicating that important differences may exist in the morphological effects of fronto-occipital reshaping from one group to another. 相似文献