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21.
Silkworm rearing has been an income source for small-holding farmers in Pakistan. Over the years efforts have been made to improve silkworm quality and quantity and thus develop better prospects for increasing yield and income. Mulberry leaves Morus alba L. in a series of experiments have been supplemented with various nutrients in different doses and combinations. Relative success has been achieved in this context. In our present experiments on silkworm Bombyx mori L., we fed the larvae on mulberry leaves supplemented with different doses of N (0.2%), P (0.1%), K (0.3%) and Ca (0.1%) at 26 ± 3°C with 65 ± 5% relative humidity. The results showed better outputs in terms of food consumption (72.55 g/10 larvae), coefficient of utilization (76.45%), body weight (70.07 g/10 larvae) and body length (8.56 cm/larvae) than where simple mulberry leaves were offered. Our net gains with these production parameters have been in terms of heavier cocoons with and without pupa (2.25 and 0.69 g/cocoon), respectively.  相似文献   
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Monoclonal antibodies were prepared against lysosomal membrane proteins of amoebae and used to follow lysosome-phagosome fusion after induced phagocytosis. The specificity of antibodies was checked by indirect immunofluorescence microscopy, immunoelectron microscopy, and localization of the antigen in subcellular fractions. The antibody-recognized proteins started to appear on the membranes of phagolysosomes about 5 min after phagocytosis as detected by indirect immunofluorescence, and the intensity of fluorescence increased for up to 1 h. Results of injection experiments in which purified antibodies had been injected into living cells and probed by indirect fluorescence indicated that the antigens were located on the cytoplasmic side of the lysosomal membranes. Lysosomes fuse with phagosomes on the one hand but not with non-fusible vesicles such as symbiosomes on the other. The results support the view that a membrane component(s) of non-fusible vesicles somehow prevents lysosomoes from fusing with them.  相似文献   
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The family Embolemidae Westwood, 1833 is recorded for the first time in Korea, based on a species Embolemus ruddii Westwood. A diagnosis of this species complemented by digital images are provided.  相似文献   
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The application of sensory methodology for measuring deodorizing effect of an air conditioner equipped with electric plasma was introduced. Deodorizing effect was measured using chemical and sensory methods at different time (0, 30 and 60 min) and mode (control, blowing and cooling) of an air conditioner. Smoke from a roll of cigarette in a closed room was used as a source of odor and the concentrations of acetic acid and ammonia were measured as odorous chemical components. As one of the sensory methods triangle test was used and as a first step to obtain deodorizing effects by triangle test, the threshold of each panelist was obtained as the log dilution ratio of odor concentration at which the difference from odorless air was detected. The odor concentration at each time and mode was calculated using the threshold of the panel and the deodorizing effect was obtained on the basis of the odor concentration. In addition to a triangle test, scaling methods such as category scaling or magnitude estimation were used to measure deodorizing effect of an air conditioner. Deodorizing effects by scaling methods were calculated based on odor intensity with time at each mode. The regression analysis was done between the efficacy of deodorizing effect by sensory test and those by acetic acid and ammonia, the R2 values of the regression equations for triangle test, category scale, and magnitude estimation were 0.84, 0.72 and 0.69, respectively. Deodorizing effect by triangle test explained the decrease of acetic acid and ammonia better than those by category scaling or magnitude estimation while high cost and time consuming labor involved in triangle tests reduced the merit. The results of this study demonstrated that various sensory methods could be used to measure deodorizing effect of air conditioners and further researches on fast and reliable methods are needed to establish the official procedures.  相似文献   
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Colonization of the roots of tobacco by Pseudomonas chlororaphis O6 induces systemic resistance to the soft-rot pathogen, Erwinia carotovora ssp. carotovara SCC1. A screen of the transposon mutants of P. chlororaphis O6 showed mutants with about a fivefold reduction in ability to induce systemic resistance to the soft-rot disease. These mutations disrupted genes involved in diverse functions: a methyl-accepting chemotaxis protein, biosynthesis of purines, phospholipase C, transport of branched-chain amino acids and an ABC transporter. Additional mutations were detected in the intergenic spacer regions between genes encoding a GGDEF protein and fumarate dehydratase, and in genes of unknown function. The mutants in the ABC transporters did not display reduced root colonization. However, the other mutants had up to 100-fold reduced colonization levels. Generally the production of metabolites important for interactions in the rhizosphere, phenazines and siderophores, was not altered by the mutations. A reduced induction of systemic resistance by a purine biosynthesis mutant with a disrupted purM gene correlated with poor growth rate, lesser production of phenazines and siderophore and low levels of root colonization. These studies showed that multiple determinants are involved in the induction of systemic resistance, with there being a requirement for strong root colonization.  相似文献   
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The microstructural organization of the silk‐spinning apparatus of the comb‐footed spider, Achaearanea tepidariorum, was observed by using a field emission scanning electron microscope. The silk glands of the spider were classified into six groups: ampullate, tubuliform, flagelliform, aggregate, aciniform and pyriform glands. Among these, three types of silk glands, the ampullate, pyriform and aciniform glands, occur only in female spiders. One (adult) or two (subadult) pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another pair of minor ampullate glands supply the median spinnerets. Three pairs of tubuliform glands in female spiders send secretory ductules to the median (one pair) and posterior (two pairs) spinnerets. Furthermore, one pair of flagelliform glands and two pairs of aggregate glands together supply the posterior spinnerets, and form a characteristic spinning structure known as a “triad” spigot. In male spiders, this combined apparatus of the flagelliform and the aggregate spigots for capture thread production is not apparent, instead only a non‐functional remnant of this triad spigot is present. In addition, the aciniform glands send ductules to the median (two pairs) and the posterior spinnerets (12–16 pairs), and the pyriform glands feed silk into the anterior spinnerets (90–100 pairs in females and 45–50 pairs in males).  相似文献   
30.
The molecular phylogeny of 12 species of Camponotus ants in Korea was examined using random amplified polymorphic DNA (RAPD) markers as inputs for an analysis of molecular variance (AMOVA) and cluster analysis to describe the relationships between species. For comparison, morphometric data (based on 10 morphological characters) were also gathered for phylogenetic analysis. Assessments of similarity between species were made, and the results of these assessments are compared for the molecular and morphological data sets. In the morphometric analysis, the following groups were identified: (i) C. atrox, C. kiusuensis, C. japonicus and C. concavus (93% similarity); (ii) C. sp. 1 (be diverging at 80% similarity); (iii) C. jejuensis, C. sp. 3, C. itoi, C. nawai and C. tokioensis (94.5% similarity); and (iv) C. nipponensis and C. quadrinotatus (94.5% similarity). Formica fusca was 73.5% similar to the 12 Camponotus species studied here. The group comprising C. nawai and C. tokioensis had the highest similarity index (97.36%), followed by the group comprising C. jejuensis and C. sp. 3 (95%), then C. atrox and C. kiusuensis (94.5%), and then C. nipponensis and C. quadrinotatus (93.5%). In the molecular analysis the following groups were identified: (i) C. atrox and C. jejuensis (30% similarity); (ii) C. concavus, C. japonicus and C. itoi (25% similarity); (iii) C. kiusuensis, C. nawai, C. sp. 3, C. nipponensis, C. quadrinotatus and C. sp. 1 (24% similarity); and (iv) C. tokioensis (be diverging at 23% similarity). The most closely related group in the molecular analysis was C. nawai and C. sp. 3 (75% similarity), followed by C. concavus and C. japonicus (50.5% similarity), then C. atrox and C. jejuensis (30%), and then C. quadrinotatus and C. sp. 1. Camponotus tokioensis was the least closely related to other species among the 12 species studied. Although C. jejuensis and C. tokioensis were found to be 93.6% similar on the basis of morphometric data, molecular data indicated only 23% similarity, the lowest similarity index between any two species considered here. Camponotus jejuensis has marked morphological similarities to C. tokioensis, but on the basis of molecular data gathered in the present study, we refute the proposal that they are synonyms or sister species.  相似文献   
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