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This paper discusses analysis of dispersion tests in tables with spoiled data, that is, where some cells are missing. BENNETT (1987) gave a method for estimating the missing cells in a two-way table and illustrated it with a simple example. This paper uses GLIM to estimate the models and indicates that the General Linear Model performs the computations without need to estimate the missing values. The binomial error model also may be used for this problem, and is the more natural approach to the problem.  相似文献   
43.

The red-striped soft scale insect Pulvinaria tenuivalvata (Newstead) (Hemiptera: Coccidae) started to infest sugarcane plants (Saccharum officinarum L.) in different districts in Egypt during the last decade. The percentage of infestation was recorded in El-Wakf area, Qena Governorate (Naghhamadi mill zone) Upper Egypt in some fields. There are three levels of infestation, low, intermediate and high. From these fields, samples were selected for physical and chemical studies. The results obtained show that the stalks of infested plants decreased in weight, the sugar content (glucose and sucrose) drastically reduced and as the percentage of infestation increased the percentage of glucose and sucrose content significantly decreased. The primary and secondary humidity and the cellulose content also increased in the healthy plants compared to the infested ones. All the physical character of the infested plants was significantly affected in comparison with the healthy ones.  相似文献   
44.
A 105-day experimental trial was conducted to assess different levels of dietary Aleo vera extract supplementation on water quality parameters, proximate composition, growth performance and haematological parameters of fry Oreochromis niloticus. Four different percentages of dietary leaf extract powder of Aleo vera (ALE) with a basal feed, designated as, i.e., T0 (Control group; without ALE), T1 (1% ALE), T2 (2% ALE), and T3 (3% ALE). Fish fry was reared in concrete tanks (7.0 m, 1.6 m, 1.0: L, W, H; water volume 11.2 m3/tank), with an average initial weight 4.04 ± 0.03 g/ fry, and each treatment was triplicated. Fry was randomly distributed at a stocking rate of 450 individuals/ tanks. The water quality parameters revealed that temperature, pH, salinity, dissolved oxygen (DO) and nitrates were found in a promising range as given by FAO/WHO limits. However, the record values obtained for Electric Conductivity (EC), Total dissolved solids (TDS), and alkalinities were not found in all tanks' suitable range according to FAO/WHO limits. The results revealed a significant impact of different percentages of dietary ALE supplementation on fry's body composition and haematological parameters. Moreover, the final body weight, final body length, average daily weight gain (g), net weight gain (g) and specific growth rate (%) were significantly higher (p < 0.05) in T1 and T2 compared with T0 and T3 treatments. The poorest feed conversion ratio was recorded in the T2 group compared with other treatments. Thus, the current study provides information about the nutritional quality of Nile tilapia culturing in Pakistan.  相似文献   
45.
Giant viruses contain large genomes, encode many proteins atypical for viruses, replicate in large viral factories, and tend to infect protists. The giant virus replication factories can in turn be infected by so called virophages, which are smaller viruses that negatively impact giant virus replication. An example is Mimiviruses that infect the protist Acanthamoeba and that are themselves infected by the virophage Sputnik. This study examines the evolutionary dynamics of this system, using mathematical models. While the models suggest that the virophage population will evolve to increasing degrees of giant virus inhibition, it further suggests that this renders the virophage population prone to extinction due to dynamic instabilities over wide parameter ranges. Implications and conditions required to avoid extinction are discussed. Another interesting result is that virophage presence can fundamentally alter the evolutionary course of the giant virus. While the giant virus is predicted to evolve toward increasing its basic reproductive ratio in the absence of the virophage, the opposite is true in its presence. Therefore, virophages can not only benefit the host population directly by inhibiting the giant viruses but also indirectly by causing giant viruses to evolve toward weaker phenotypes. Experimental tests for this model are suggested.  相似文献   
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The aim of the present study is to clarify the taxonomic position of Teucrium euganeum Vis. vis à vis T.siculum (Rafin.) Guss. and T.scorodonia L. The study is based on an analysis of macro- and micro-morphological characters, type, and distribution of trichomes in different parts of the plant, chromosome counts, and a statistical analysis of such morphometric data. The results of the study allow one to consider the populations of the Euganean Hills (Padua, north-eastern Italy) as a sub-species of T.siculum, and, therefore, a new combination is proposed: Teucrium siculum (Rafin.) Guss. subsp. euganeum (Vis.) Tornadore, comb. et stat.nov.  相似文献   
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目的:探讨结直肠癌中IGF-Ⅱ、IGF-l R以及IGFBP-3等的阳性表达及诊断价值。方法:收集我院45例结直肠癌、33例炎性息肉、40例腺瘤以及35例正常肠粘膜组织予以免疫组织化学SP法进行IGF-Ⅱ、IGF-l R以及IGFBP-3检测,并统计结直肠腺瘤不同组织类型和结直肠癌不同Dukes分期的阳性表达差异。结果:结直肠癌组织中IGF-Ⅱ、IGF-l R以及IGFBP-3表达均呈高阳性率,并且显著高于其他3组(P0.05)。结直肠腺瘤管状、混合型、绒毛状等不同组织类型IGF-Ⅱ、IGF-l R以及IGFBP-3表达阳性率呈逐渐增高趋势,绒毛状腺瘤显著高于其他两型(P0.05)。45例结直肠癌中,Dukes分期A、B两期显著低于C期和D期,比较差异具有显著性(P0.05)。结论:IGF-Ⅱ、IGF-l R以及IGFBP-3可能在结直肠腺瘤发生、发展及进展为结直肠癌的过程中起一定作用,对结直肠癌早期诊断具有一定价值。  相似文献   
50.
The morphology of the venomous limbs (forcipules) of 13 species of Strigamia and of six other geophilomorphs was studied with light microscopy, scanning electron microscopy, and, for a subsample, with confocal laser scanning microscopy. In all Strigamia species a well-distinct denticle is present invariantly on the inner side of the terminal article (tarsungulum), in sub-basal position, just proximal to a faint transverse sulcus and a cuticular introflexion that corresponds to the insertion point of a tendon. Strigamia species differ mainly in size and shape of the denticle and thickness of the distal part of the tarsungulum, suggesting some functional diversity in piercing and handling prey. Anatomical evidence supports the hypothesis that the tarsungulum corresponds to two ancestral articles and a denticle at the basis of the tarsungulum originated multiple times within geophilomorphs, however in different positions corresponding to either the ancestral sub-terminal article (in Strigamia, other Geophiloidea and some Schendylidae) or the ancestral terminal article (in the himantariid Thracophilus).  相似文献   
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