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1.
Kazuo Nakamura 《Population Ecology》1972,14(1):82-96
To express the degree of hunger during both of feeding and unfeeding periods of spiders, equations for the amount of ingestion and food disappearance from the gut were presented using three components: capacity of gut, rate of ingestion and rate of food disappearance. The degree of hunger was expressed by the rate of unfilled capacity of gut to the capacity of gut based on these equations. The rates of ingestion and food disappearance were estimated from the results of experiment with a wolf spider, Pardosa laura. The equations obtained well applied to the experimental result. By changing values of these rates, it was revealed that the ratio of rates of ingestion to food disappearance determine the amount of ingestion. 相似文献
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Population Ecology - Survival times and changes in the respiratory rates and the live body weights of a predaceous lady beetle,Coccinella septempunctata bruckii Mulsant, and a phytophagous lady... 相似文献
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The population parameters of green rice leafhopper, Nephotettix cincticeps in hibernated generation was estimated by the capture-recapture method on the gramineous weeds of resting paddy field from late in April to mid-May, 1962–1965. The difficulty of applying the capture-recapture method to this insect is caused from the low density and the low activity of the leafhopper, so that it is necessary to make the suitable plan of capture-recapture series and to construct the special method to detect the population parameters. The number of adults differed greatly among the years and among the plots in the same year. But, in general, the density was relatively high late in April, and decreased rapidly in May. The number of males was higher than that of females late in April, but decreased rapidly to become lower in May. The sampling efficiency with sweep-net depends upon the many factors, such as weather and floristic conditions; especially the atmospheric temperature and the force of wind are considered to affect greatly to the efficiency. In general, low temperature and strong wind are the cause of low sampling efficiency. 相似文献
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ROBERT R. JACKSON 《Zoological Journal of the Linnean Society》1986,88(2):179-190
Myrtnarachne is a genus of ant-like salticids. Eight species were observed feeding, in nature, in Australia, Kenya, Malaysia and Sri Lanka, on varied types of insects but not ants. The behaviour of M. lupata , from Australia, was studied in the laboratory. Predatory sequences were found to differ considerably from those of typical salticids. Attacking by lunging instead of leaping and the pronounced use of pre-attack tapping are especially noteworthy. The unusual behaviour of M. lupata when preying on insects is consistent with maintenance of ant mimicry. Myrmarachne lupata also preys on the eggs of other spiders which it extracts from their nests. The males of many species have very large chelicerae, and the large chelicerae of M. lupata males influence the course of predatory sequences, with insects and with eggs. 相似文献
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Population Ecology - Survival rates and mortality factors of a migrant skipperParnara guttata were censused in paddy fields in 4 localities of central and western Japan during 1975–1980, and... 相似文献
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生殖量是生殖潜力(reproductivepotential)的一个主要标志,也是生态系统(含生产力)和种群生态学(含数量变动)的一个主要内容。它在很大程度上是由遗传因子(基因)决定的,表现在各类动物的生殖量有很 相似文献
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甘蓝型油菜芥酸和二十碳烯酸含量的基因效应 总被引:3,自引:0,他引:3
以甘蓝型油菜的4种纯合芥酸基因型之间所有可能的6个杂交组合的P_1、P_2、F_1、P_2、B_1和B_2世代为材料,用生统遗传学方法研究了芥酸和二十碳烯酸的基因作用形式及效应。发现无论亲本是单基因差异还是二基因差异,F_1和F_2代的芥酸含量都接近中亲值,F_1略大于中亲值和F_(20)世代均值分析表明,芥酸含量的遗传符合加性显性模型,加性效应占绝对优势,显性效应不显著。用数量遗传学方法估计的芥酸基因数与已知的结果相近。 相似文献
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Food is a limiting factor for the deposit feeders. The availability of sediment nutrients thus has a tight relationship with the growth, survival and development of the animal. There are two purposes of this study: (1) to determine if the ingestion and growth rates can be used as a bioassay approach to assess the sediment nutrients; and (2) use the combination of bioassay approaches and chemical analyses to determine which chemical parameter is the better predicator of the sediment nutrients to the animals. In the preliminary study, the optimal growth length and average ingestion rate of Capitella sp. I were obtained from the laboratory. The standardized relationships of the growth and ingestion rates in response to different nutrients were prepared. Then, the sediments collected from different coastal wetlands in Western Taiwan were used in the feeding, growth experiments and chemical analyses. The comparisons were made between the field and laboratory experiments to determine the sediment nutrients in the wetland of Taiwan. In the growth rate standardized relationship, Capitella sp. I increased its growth rate with the total organic nitrogen (TON) concentration between 0 to 2.8 mgN·g sediment−1, total organic carbon (TOC) concentration between 0 and 22.4 mgC·g sediment−1, and enzymatically hydrolyzable amino acid (EHAA) concentration between 0 and 4.48 mg protein·g sediment−1. After the nutrient concentrations exceed these values, the growth rates decreased gradually. In the ingestion rate standardized relationship, the animal increased its ingestion rate with the total organic nitrogen (TON) concentration between 0 and 2 mgN·g sediment−1, total organic carbon (TOC) concentration between 0 and 14.1 mgC·g sediment−1, and EHAA concentration between 0 and 3.2 mg protein·g sediment−1. After the nutrient concentrations exceed these values, the ingestion rates also decreased. To determine which nutrient parameter is the best predictor for the sediment nutrient in the field, we first analyzed whether the data obtained from the laboratory fell within 99% confidence interval of the regression obtained from the field data. Then, to determine which parameter had the shortest perpendicular distance between the field and the laboratory regression curves. Both the growth and ingestion rates comparisons showed that the EHAA is the best candidate of the sediment nutrient of deposit feeders in the field. The results of this study proved tentatively that the growth and ingestion rates of Capitella sp. I can be used as the bioassay approaches to estimate the sediment nutrients. The combination of the bioassay approaches and the relevant chemical analyses allows us to determine the bioavailability fraction of sediment to the deposit feeders. 相似文献
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Mazumdar S Bhattacharyya S Ghosh S Majumdar S Ganguly NK 《Molecular and cellular biochemistry》2007,297(1-2):9-19
An immunodominant heat shock protein (Hsp 24) was purified from Vibrio cholerae O139 at 42 degrees C and used as an immunomodulator for studying the gut immune response. T cell clone and T cell line specific for the Hsp 24 were generated from the lymphocytes of lamina propria and intra-epithelial lymphocytes of mice orally infected with V. cholerae O139, respectively. The T cell clone was TCR alphabeta(+), CD4(+) and appeared to play an important role in the functioning of gut B-lymphocytes. The T cell line had heterogenous population of CD8+ and CD4+ cells, most of which were found to be TCR alphabeta(+) and a minor population was TCR gammadelta(+). The lymphokine profile of T cell line showed IFN-gamma to be the most abundant lymphokine followed by IL-2 and IL-4. The possible involvement of alternative pathway of activation for T cell clone was also addressed in this study. The splenocytes showed an up-regulation of their CD2 receptor expression on stimulation with the Hsp-24. The pattern of lymphokines released by splenocytes stimulated with the Hsp-24 showed no particular cell type to be responsible for mounting immune response. Thus, there is involvement of both, mucosal and peripheral arm of the immune system. 相似文献
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Se Sil Lee Hyobin Seo Sungpil Ryu Tae-Dong Kwon 《Journal of Exercise Nutrition & Biochemistry》2015,19(3):235-245
Purpose
The purpose of this study is to observe the effects of Salicornia herbacea L. powder ingestion on carbohydrate metabolism in STZ-induced diabetic rats.Methods
To achieve this objective, 35 Sprague-Dawley male rats were raised with feed mixed with Salicornia herbacia L. powder and given specific periods to swim for 5 weeks. There was no significant difference in the insulin increase rate while ingesting Salicornia herbacea L. powder and simultaneously exercising.Results
Compared to the diabetes mellitus group, HOMA-IR was significantly decreased in the diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and the diabetes mellitus + Salicornia herbacea + exercise group. However, changes in blood glucose were significant in each group. Thus, for the result of GLUT-4 and GLUT-2, which are the glycose transporters of the liver and muscle, diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and diabetes mellitus + Salicornia herbacea + exercise group showed significantly higher expressions. The glycogen concentration of the liver and muscle was significantly increased in the diabetes mellitus + exercise group, diabetes mellitus + Salicornia herbacea group, and diabetes mellitus + Salicornia herbacea + exercise group.Conclusion
With the results above, it seems that taking Salicornia herbacea L. powder and exercise will help prevent various diabetic complications. Therefore, the findings of this study could justify Salicornia herbacea L. powder with its basal data of physiological activities and pharmacological components as a type of health functional food. 相似文献14.
The orthomolecular treatment of cancer. I. The role of ascorbic acid in host resistance 总被引:4,自引:0,他引:4
Natural resistance to neoplastic disease governs the incidence of clinical cancer and influences the individual's response to standard methods of treatment. Supportive measures, specifically designed to enhance the natural resistance of the host, should diminish cancer incidence, morbidity and mortality. The various factors involved in host resistance are briefly reviewed, and it is contended that the availability of ascorbic acid plays an important role in many of these physiological processes. The potential value of ascorbic acid in the supportive treatment of cancer is a matter for urgent study at many levels. It offers the promise of general improvement in the results of cancer management, including prophylaxis in general, supportive therapy when standard methods of treatment are being used, and palliative treatment in advanced terminal cancer. 相似文献
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von Korff M Wang H Léon J Pillen K 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(3):583-590
The objective of this study was to map new resistance genes against powdery mildew (Blumeria graminis f. sp. hordei L.), leaf rust (Puccinia hordei L.) and scald [Rhynchosporium secalis (Oud.) J. Davis] in the advanced backcross doubled haploid (BC2DH) population S42 derived from a cross between the spring barley cultivar Scarlett and the wild barley accession ISR42-8 (Hordeum vulgare ssp. spontaneum). Using field data of disease severity recorded in eight environments under natural infestation and genotype data of 98 SSR loci, we detected nine QTL for powdery mildew, six QTL for leaf rust resistance and three QTL for scald resistance. The presence of the exotic QTL alleles reduced disease symptoms by a maximum of 51.5, 37.6 and 16.5% for powdery mildew, leaf rust and scald, respectively. Some of the detected QTL may correspond to previously identified qualitative (i.e. Mla) and to quantitative resistance genes. Others may be newly identified resistance genes. For the majority of resistance QTL (61.0%) the wild barley contributed the favourable allele demonstrating the usefulness of wild barley in the quest for resistant cultivars. 相似文献
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Brian a. Maurer 《Evolutionary ecology》1998,12(8):925-934
The hypothesis that evolution of body size in birds was a random process coupled with an absolute lower boundary on body mass was tested using data on 6217 species of extant birds. The test was based on the fact that subclades within birds that have body masses much larger than this minimum should not have skewed log body mass distributions, while clades close to this boundary should. Bird species were classified into 23 orders suggested by Sibley and Monroe (1988). Thirteen orders that had average log body masses greater than the average for all birds had significantly skewed log body mass distributions. This is inconsistent with the hypothesis that evolution of body size in birds is random, but is constrained only at the smallest body masses. Most orders of birds cannot be considered random samples from the parental distribution of all birds. When the pattern of body mass evolution in birds is reconstructed using an estimate of the phylogenetic relationships among orders, there are many more instances where a large taxon putatively originated from a smaller one than vice versa. The non-random nature of body mass evolution in birds is consistent with models that postulate that evolution is constrained by the ability of individuals to turn resources into offspring. 相似文献
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Abstract A study of the growth of the maritime halophyte Aster tripolium L. has been carried out over a range of salinity treatments. The regression approach to growth analysis using frequent small harvests has been used to allow ‘continuous’ measurement of growth over a period of 36 d. Salinity was applied with the major ions present in ratios typical of those found in seawater. Growth was inhibited in terms of both dry weight production and leaf expansion at salinity levels equivalent to 0.625 strength sea water (full culture solution 300) and above, with the greatest effect being seen in terms of leaf area. Aster tripolium did not show increased succulence at high salinity, leaf fresh weight to dry weight ratio in fact declined, whilst leaf fresh weight per unit area remained constant. It should be noted that the plants exhibit low growth rates due to the low light intensity used. 相似文献
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The dye spectrophotometric method for the measurement of the activity of divalent metal ions in polyelectrolyte solutions containing added electrolytes is discussed.The method is applied to mixtures containing the dextransulfate polyanion, NaCl, and MgCl2 or Ca2. A two wavelength ratio method as applied to polyelectrolyte solutions is compared to the standard method which makes use of the previous determination of the dye-metal ion formation constant. The ratio method is found to be a convenient and reliable method which is not influenced by decomposition of the dye or by statistical errors in the extrapolation procedure. The activity coefficients as determined by the two wavelength dye spectrophotometric method are compared to results of Donnan exclusion measurements, and of EMF measurements using a calcium ion selective electrode. The results of the spectrophotometric method are equal to those of the two other methods within the limits of error in the latter. The spectrophotometric measurements can extend to much lower ion activaties than the other two methods, and can be done in the presence of a large excess of added electrolyte, yielding results of considerably improved precision when compared to Donnan and EMF methods. 相似文献
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The chick oviduct in tissue culture. I. Initial characterization of growing primary oviduct tissue cultures 总被引:1,自引:0,他引:1
A simple three-enzyme treatment of collagenase, dispase and hyaluronidase on finely minced chick oviduct yields clumps of 50-150 cells. These cells attach to collagen-treated dishes and survive in culture for at least 2 weeks without subculturing. Oviduct cell cultures can also be induced to grow. Estradiol or epidermal growth factor (EGF) induce a 40% increase in cells in 4 days when cultures are grown in serum levels that do not support growth. Serum from estrogen-stimulated chicks promotes rapid cellular proliferation (doubling times of 1-2 days). Sera from estrogen withdrawn chicks, laying hen or horse do not support as rapid proliferation. The oviduct growth-promoting factors in serum from estrogen-stimulated chicks are not steroids or fibroblast growth factors (FGF). Removal of steroids from these sera by charcoal treatment or delipidization does not decrease the rate of growth. The addition of 1-100 nM estradiol does not increase a serum's ability to promote growth. Purified FGF or platelet-derived growth factor (PDGF) do not induce oviduct proliferation. These results were reproduced in oviduct cell cultures started from estrogen-stimulated and withdrawn chicks as well as laying hens. Thus the factors in serum from estrogen-stimulated chicks that promote rapid oviduct growth are induced by estrogen treatments in vivo, but do not seem to be only steroids. 相似文献
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H. X. Wu A. C. Matheson D. Spencer 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(8):1256-1268
The effects of inbreeding on growth, survival and variance in a 12-year-old radiata pine trial were studied in five populations
each inbred to one of five different levels: outcross (F=0), half-sib (F=0.125), full-sib (F=0.25), selfing (S1, F=0.5), and two-generations of selfing (S2, F=0.75). These five populations were derived from a founder population of eight clones. Inbreeding reduced diameter, growth,
and survival but increased the variance for diameter. Inbreeding depression at F=0.125, 0.25, 0.5, and 0.75 was 5%, 6%, 15%,
and 19% respectively for DBH; −3%, 1%, 7%, and 11% respectively, for survival. The standard deviation for diameter increased
by 10%, 10%, 30%, and 25% respectively for F=0.125, 0.25, 0.5, and 0.75 and, similarly, the coefficient of variation increased
by 17%, 16%, 53%, and 55% respectively. There were significant differences among the eight founder clones in their response
to inbreeding. The best clone in the trial showed no inbreeding depression. Overall, inbreeding depression was found to be
linearly related to the inbreeding coefficient F with no significant quadratic effects for any trait at any population level.
However, two individual clones had a quadratic relationship with F for DBH and one clone had a similar relationship for survival.
A significant correlation (r=0.96) between S2 and the breeding values of founder clones was observed while the correlation (r=0.58) between S1 and breeding values was insignificant. The low inbreeding depression in radiata pine relative to other conifers may indicate
that historical purging of detrimental alleles through small geographic populations, a higher degree of population subdivision,
and the relative high fecundity of inbred progenies has rendered radiata pine an ideal species to use inbreeding as a breeding
tool.
Received: 10 March 1998 / Accepted: 19 May 1998 相似文献