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1.
Distribution and strain-dependent formation of volatile metabolites in the genus Ceratocystis 总被引:1,自引:0,他引:1
The accumulation of volatile metabolites in cultures of 34 strains comprising ten species of the genus Ceratocystis (Ascomycetes) has been investigated under defined culture conditions. The identified compounds include short-chain alcohols and esters, lower terpenes, terpenoids, and 2-phenylethyl acetate. Certain species can be recognized by a number of common volatiles traced in all strains, although the quantities of these constituents may vary enormously (up to a factor 1:1000) within one species. The formation of some metabolites is restricted to a few strains. 相似文献
2.
The species composition of aquatic insects in theboreal stream, Skiftesåa, was investigated usingemergence traps, Malaise traps and kick samples. Atleast 13 Ephemeroptera, 16 Plecoptera, 25 Trichopteraand 120 Chironomidae species were recorded. This faunais representative for non-polluted, northern streams.The production of macrobenthos was estimated to beonly about 1 g dry weight per year and m2,possibly due to the fluctuating flow of water. 相似文献
3.
Hans-Peter Hanssen 《Phytochemistry》1982,21(5):1159-1160
Several sesquiterpene hydrocarbons, mainly of the cadinane skeleton, have been identified in cultures of the brown rot fungus Lentinus lepideus. The main compounds are δ-cadinene, α- and γ-muurolene. 相似文献
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The breeding performance of captive willow ptarmigan on different diets has been studied. The nutritional factors tested were protein concentration, natural feed supplement and grass meal and flavonoid admixture, and effects on egg numbers, fertility, hatchability, chick weights at hatching and 0–14 days mortality have been recorded. The breeding performance of ptarmigan hen in captivity showed great individual variations. Egg numbers were not statistically different in groups fed the different diets. Hens fed a 15 % crude protein died tended to produce smaller chicks with significantly lower viability than chicks from hens fed a 20 % crude protein diet. Supplement of natural feed tended to increase the number of chicks hatched through a combination of tendency to higher egg numbers and improved fertility. These tendencies were, however, statistically nonsignificant. Inclusion of 34 % grass meal to the diet also tended (non-significantly) to improve fertility and hatchability, while inclusion of flavonoids had no positive effect on reproduction. Eggs from captive hens showed significantly lower fertility, and a tendency to lower hatchability than eggs from wild hens. The former difference was probably caused by the close cage confinements for the captive ptarmigan, while the latter condition probably was due to different start of incubation, most of the eggs from wild hens being started naturally. 相似文献
6.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs. 相似文献
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In Dutch, variation occurs in the formation of noun-noun compound words. Some compounds always add the linking element -en- between the two nouns; some compounds never use such a linking element; and still others allow both options. The element -en- is homophonous with the regular plural ending in Dutch, and we therefore investigated if plural semantics creates a preference for the linking element -en- in novel Dutch noun-noun compounds. We also investigated if the preference for linking -en- is influenced by just meaning (i.e., a semantic plural), form (i.e., a formal plural), or perhaps both. The influence of native language on preferences for Dutch compounds was also investigated. In study 1, we tested native speakers of Dutch; in study 2, Frisian-Dutch bilinguals; and, in study 3, speakers of German with Dutch as a second language. Plurality played a role in the preferences for Dutch compound formation in all tested groups. For native speakers of Dutch, Frisian, and German, moreover, the preference for a linking element in novel Dutch compounds was influenced by both the semantic plural and the formal plural. However, these effects were smaller for the native speakers of German. These findings confirm the findings of earlier studies (e.g. Schreuder et al. in Language and Cognitive Processes 13(5):551–573, 1998) showing linking -en- to carry an intrinsic plural meaning. Kiparsky’s level-ordering hypothesis (Linguistics in the morning calm, pp. 3–91, 1982) and Pinker’s words-and-rules theory (Words and rules: the ingredients of language, 1999) are re-considered in light of the present findings. 相似文献
10.
AB Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(4):261-268
Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight. 相似文献