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141.
Microclones of different mulberry genotypes were successfully transferred to the field. The same genotypes were raised through
conventional methods (cuttings). A comparative study using morphological and biochemical tests of field established micropropagated
and cutting derived plants of mulberry genotypes was conducted. Micropropagated mulberry plants showed significant morphogenic
vigour when compared to plants raised through cuttings. Biochemical tests of leaves revealed that, there was no significant
nutritional difference between micropropagated plants and those originated from cuttings.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
142.
Unconditional Exact Tests for Equivalence or Noninferiority for Paired Binary Endpoints 总被引:2,自引:0,他引:2
Problems of establishing equivalence or noninferiority between two medical diagnostic procedures involve comparisons of the response rates between correlated proportions. When the sample size is small, the asymptotic tests may not be reliable. This article proposes an unconditional exact test procedure to assess equivalence or noninferiority. Two statistics, a sample-based test statistic and a restricted maximum likelihood estimation (RMLE)-based test statistic, to define the rejection region of the exact test are considered. We show the p-value of the proposed unconditional exact tests can be attained at the boundary point of the null hypothesis. Assessment of equivalence is often based on a comparison of the confidence limits with the equivalence limits. We also derive the unconditional exact confidence intervals on the difference of the two proportion means for the two test statistics. A typical data set of comparing two diagnostic procedures is analyzed using the proposed unconditional exact and asymptotic methods. The p-value from the unconditional exact tests is generally larger than the p-value from the asymptotic tests. In other words, an exact confidence interval is generally wider than the confidence interval obtained from an asymptotic test. 相似文献
143.
Glucoamylase (1,4-α-d-glucan glucohydrolase, EC 3.2.1.3) has been covalently immobilized on a polyacrylamide-type support containing carboxylic groups activated by water-soluble carbodiimide. The activity was 5.5– 6.0 units g?1solid. The optimum pH for catalytic activity was pH 3.8. The apparent optimum temperature was found at 60°C. With soluble starch as substrate the Km value was 14 mg ml?1. The pH for maximum stability was pH 4.0–4.5. In the presence of 8 m urea the immobilized glucoamylase retained most of its catalytic activity but it was more susceptible to guanidinium hydrochloride than the soluble enzyme. The practical applicability of immobilized glucoamylase was tested in batch process and continuous operation. 相似文献
144.
Lifespan and patterns of accumulation and mobilization of nutrients in the sugar-fed phorid fly, Pseudacteon tricuspis 总被引:2,自引:0,他引:2
Henry Y. Fadamiro LI Chen Ebenezer O. Onagbola Lawrence 'FUDD' Graham 《Physiological Entomology》2005,30(3):212-224
Abstract. The effect of sugar feeding on the survival of adult phorid fly Pseudacteon tricuspis is investigated. Flies fed 25% sucrose in aqueous solution continuously throughout their lifespan have greater longevity (mean ± SE longevity: female = 7.9 ± 0.8 days, male = 8.9 ± 0.9 days) than completely starved (provided no water and no sugar solution) flies, sugar-starved (provided water only) flies, or flies fed sugar solution only on their first day of adult life. Completely starved flies rarely lived beyond one day. Provision of water increases longevity by 2 days, and one full day of sugar feeding further increases longevity by an additional 1–2 days. Flies fed 50% sucrose have similar survivorship as those fed 25% sucrose. The temporal patterns of nutrient accumulation and utilization are also compared in P. tricuspis fed different diets: sugar-starved, sucrose-fed on the first day of adult life only, and sucrose-fed continuously. Adult P. tricuspis emerge with no gut sugars, and only minimal amounts of body sugars and glycogen. Although the levels of body sugars and glycogen decline gradually in sugar-starved flies, a single day of sugar feeding results in the accumulation of maximum amounts of gut sugars, body sugars and glycogen. High levels of these nutrients are maintained in female and male phorid flies fed on sucrose continuously over the observation period, whereas nutrient levels decline in flies fed only on the first day of life, beginning 1 day postfeeding. Female and male P. tricuspis emerge with an estimated 12.3 ± 2.3 and 7.2 ± 1 g of lipid reserves per fly, respectively. These teneral amounts represent the highest lipid levels detected in adult flies, irrespective of their diet, and are maintained over the life times of sucrose-fed female and male flies, but declined steadily in sugar-starved females. These data suggest that adult P. tricuspis are capable of converting dietary sucrose to body sugars and glycogen, but not lipids. 相似文献
145.
Giacinto S. Germinara Abubaker Elgargoti Antonio De Cristofaro & Giuseppe Rotundo 《Entomologia Experimentalis et Applicata》2007,124(2):213-219
The female‐produced sex pheromone of the Durra stem borer, Sesamia cretica (Lederer) (Lepidoptera: Noctuidae), had been previously characterized as a 75:25 blend of (Z)‐9‐tetradecenol (Z9‐14:OH) and (Z)‐9‐tetradecenyl acetate (Z9‐14:OAc) based on field trapping experiments. The low attraction of this blend in the field led us to further investigate the sex pheromone of this pest. Coupled gas chromatography with electroantennographic detection (GC‐EAD) analysis of female pheromone gland extracts consistently revealed three EAD‐active compounds. According to their GC retention times, mass spectra, and comparative EAG analyses with authentic standards, two of these compounds were found to be the previously reported components Z9‐14:OH and Z9‐14:OAc, whereas a third compound was identified as (Z)‐11‐hexadecenol (Z11‐16:OH). In wind tunnel experiments, the highest male responses were elicited by ratios of Z9‐14:OH, Z9‐14:OAc, and Z11‐16:OH, ranging from 90:1:9 to 90:5:5. In field tests, the 90:1:9 ratio of the blend loaded onto rubber septum dispensers was significantly more effective than single‐component, two‐component, and any other ratio of the three‐component blend. The greater effectiveness of this blend resulted in a more accurate detection of S. cretica flight activity compared with the previously reported two‐component blend. 相似文献
146.
147.
148.
The pesticides carbendazim (CA), imidacloprid (IM), and thiophanate-methyl (TH) are used extensively in apple production. However, the presence of pesticide residues in apples has been associated with a wide range of human health hazards. To assess whether apples are safe to consume, evaluating their potential health risk is of great significance. We tested apples from two dominant apple-producing areas for the presence of pesticide residues and constructed a statistical model to evaluate their health risks. Of the three commonly used pesticides, thirty-two samples (11.3% of all tested samples) were residue-free and 231 (81.9%) contained CA residues, which was the most frequently detectable pesticide, followed by TH (52.1%) and IM (39.0%). All of the samples were below the maximum residue limits. The probabilistic assessment results indicated that the pesticide intake risks for kids (aged 2–6 years) and children (aged 7–13 years) were significantly higher than those of other groups, so that they were the vital monitoring objects. Our findings indicate that consumption of apples with these three pesticides does not pose a health threat for the population. Nevertheless, we recommend an investigation into continuous monitoring and stricter regulations on fruits' quality and safety throughout China. 相似文献
149.
In many clinical trials, it is desirable to establish a sequential monitoring plan, whereby the test statistic is computed at an interim point or points in the trial and a decision is made whether to stop early due to evidence of treatment efficacy. In this article, we will set up a sequential monitoring plan for randomization-based inference under the permuted block design, stratified block design, and stratified urn design. We will also propose a definition of information fraction in these settings and discuss its calculation under these different designs. 相似文献
150.