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131.
This paper provides a review of the family Lucanidae in Korea, which consists of 17 species belonging to 9 genera. One new species, Dorcus tenuihirsutus sp. nov., is described and the following taxonomical changes are proposed: Aegus laevicollis Saunders, 1854 is newly identified as Aegus laevicollis subnitidus Waterhouse, 1873; Macrodorcas striatipennis Motschulsky, 1861 is removed from the Korean fauna because this record is thought to have been based on the misinterpretation of locality and misidentification; Neolucanus saundersii Parry, 1864 is removed from the Korean fauna because this record is thought to have been based on misidentification.  相似文献   
132.
1. Duckweed (Lemna minor), collected either in summer or early fall was exposed under laboratory conditions to control (photosynthetically active and UV‐A radiation) or experimental (control plus UV‐B radiation) conditions. 2. Growth and survival were determined by counting the number of green, and brown/white fronds following 1–5 or 11 days of irradiation. Growth of duckweed was impaired by exposure to UV‐B radiation in the fall experiment but not in the summer. 3. Fatty acid compositions were analysed following 5 or 11 days of irradiation and a recovery period of 0, 5, 29 or 40 h. Concentrations of the major fatty acids, palmitic, linoleic (LA) and α‐linolenic (ALA) acids were similar in the summer and fall duckweed collections, but the summer samples had higher concentrations of the desaturation products of LA and ALA. 4. UV‐B exposure had small, but significant, and contrasting effects on duckweed fatty acid concentrations. In the summer experiment, duckweed exposed to UV‐B had slightly lower concentrations of major fatty acids than control duckweed, while the reverse was true in the fall experiments. 5. These minor effects of UV‐B on concentrations of LA and ALA would be unlikely to have a major impact on the supply of these essential fatty acids from duckweed to freshwater food webs.  相似文献   
133.
Eleven polymorphic dinucleotide (GA and CA) microsatellites were isolated and characterized in the mosquito Anopheles sinensis; this species is distributed over the East Asia region and is a primary vector of malaria, particularly in Korea. The number of alleles per locus ranged from 4 to 13. The observed heterozygosity (HO) and expected heterozygosity (HE) varied from 0.30 to 0.89 and from 0.59 to 0.90, respectively. These microsatellites could be useful in studying the evolution of the widely distributed A. sinensis in diverse environments.  相似文献   
134.
The Plus ça change model predicts that deepwater trilobite species such as Triarthrus should exhibit gradual phyletic evolution. A detailed stratigraphic sequence of Triarthrus beckii specimens considered together with geographically separated samples from a single time interval provide a test of the Plus ça change model. We examined geographic patterns of variation in cranidial shape based on specimens from four approximately synchronous levels within the Upper Ordovician (lower Edenian) strata of New York, Québec, Kentucky and Pennsylvania. All geographic populations differ in mean size, except for New York and Pennsylvania. Because allometry is present in both meraspid and holaspid phases of the trilobite, size effects on shape were removed by ontogenetic standardization. Cranidial shapes were then compared among the four study sites and eight stratophenetic samples from New York, obtained by subdividing our Mohawkian Composite Standard Section into 20-m-thick intervals. Goodall's F-test of pairwise comparisons of cranidial shape between eight subintervals in New York and the other three populations are all significant. Geographic variation in cranidial size and shape in T . beckii appears to display a gradient or cline-like pattern that is related to paleogeography. Although cranidial shape is not entirely static within the New York stratophenetic series, it is in all cases different from that sampled elsewhere in the region. Thus, there is no evidence of wholesale immigration and emigration among the geographic areas. Instead, the geographic gradient of T . beckii shape variation may have remained fairly stable over ca. 3 million years during the mid-Chatfieldian to early Edenian interval. This result is indicative of stasis. Consequently, the evolutionary history of T . beckii contradicts the Plus ça change model.  相似文献   
135.
Toxicity of 4-nonylphenol (4-NP) in the Chironomidae Chironomus flaviplumus was analyzed using a proteomics approach that involved identifying proteins by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Proteome analysis of 4-NP-treated samples on silver stained gels found alterations in the expression levels of three proteins compared with control samples. Hsp70 proteins, so-called stress proteins, were studied in Chironomus flaviplumus exposed to different concentrations of 4-nonylphenol (0, 30, 100, 150, 300 and 600 mg/L) in the laboratory and in the field in captured animals from site 1 (1 km from a chemical factory) and site 3 (16 km from a chemical factory). Hsp70 proteins were found in all samples tested, including controls, but differed in their expression levels. At more polluted sites (site 1), the samples treated with higher concentrations of 4-NP more strongly expressed Hsp70. 2-D spots were induced or enhanced in gels following injection of 4-NP. Therefore, the induction of stress protein expression in Chironomus flaviplumus, in particular Hsp70, can be used as a biomarker for the evaluation of environmental conditions.  相似文献   
136.
137.
Chironomidae is usually the most abundant macroinvetebrate in freshwater. They form an important part of the foodweb, and also have long been known as indicators of water quality. However, there is a great deal of difficulty in its identification. Such is due to the complexity of larval taxonomy. The external fine structures of the mouth parts and antennae of 4th instar larva C. flaviplumus and C. salinarius were examined using scanning electron microscopy (SEM). The antennae of the fourth instar larvae of C. flaviplumus and C. salinarius are short and composed of five segments. They consist of a scape, pedical, and three flagellar subsegments. The maxilla palps have 10 sensilla basiconica on its distal surface. They show the three morphological groups in the following numbers: six apical sensillae, three medial sensillae, and one lateral sensillae. The mandibles have strong apical and lateral teeth. These sensory structures are situated on the head capsule, each of which are represented with images to elucidate the identification of chironomidae.  相似文献   
138.
Repellent efficacies of two natural aroma compounds, citronella and citronellal, against mosquitoes, Culex pipiens pallens, were evaluated both in field and in vitro. In vitro, the experiment was conducted with three controlled bands impregnated with 30% citronella extract, 15% citronella extract and 30% citronellal extract, and with bands impregnated 30% citronella in field. Data was obtained by the means of counting numbers bitten by mosquitoes per unit time, namely human bait method. Percentage repellencies of above three controlled bands were calculated at 86%, 73%, and 78%, respectively in vitro, and 80% in field, showing high repellent effectiveness against mosquitoes. This estimation was also confirmed by t‐test compared between control group and each experimental group.  相似文献   
139.
Fatty acid synthesis from [14C]acetate was studied in the brownalgae, Fucus serratus and Fucus vesiculosus, which had beencollected from sites polluted by run-off from old copper mines.Algae collected from areas exposed to copper in situ showedchanges in the pattern of fatty acids labelled in vitro withan increase in oleate labelling and a decrease in palmitatelabelling in both species. The endogenous fatty acid patternsfor algae from polluted sites also differed from those fromunpolluted sites. Algae from sites polluted by copper containedmore oleate than samples from non-polluted sites. In addition,there were decreases in the polyunsaturated fatty acids -linolenate,octadecatetraenoate and docosapentaenoate for copper-exposedalgae. These differences are discussed with regard to the possiblemetabolic site of copper's action and to the relative toleranceof Fucus spp. to high environmental dissolved copper levels. Key words: Fucus spp., Copper pollution, Fatty acid synthesis  相似文献   
140.
1. Terrestrial plant litter entering two forest and two pasture sites on upland streams in south-eastern Australia was measured over a 2-year period using traps suspended above the streams. Laterally transported terrestrial plant litter was also determined in one stream, but found to be only 10% of the total. 2. Litter accession to traps suspended above the stream was significantly lower at both forested sites than was litter fall in the adjacent riparian vegetation. 3. Litter input was high (600–700g DW m?2yr?1) and seasonal, with 30–50% of the annual total entering the stream during December—February (summer). However, seasonality was not as great as that recorded in Northern Hemisphere deciduous forest streams. 4. Leaves comprised the largest litter component, but represented a relatively smaller proportion of the litter than is usually the case in Northern Hemisphere deciduous forest streams; in contrast bark was a relatively large proportion of the litter. 5. At the sites flowing through pasture, litter accession was about two orders of magnitude lower than at the forested sites.  相似文献   
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