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1.
Dispersal of adult Trichoptera at a Danish forest brook 总被引:3,自引:0,他引:3
- 1 The dispersal of adult Trichoptera at the small Danish forest brook, Stamperenden, was studied from 10 May to 6 October 1990 using Malaise traps placed across the brook, parallel to the brook at distances of 2, 20 and 40m, and perpendicular to it at a distance of 1–3m.
- 2 Of the total of 4175 specimens caught, lotic species breeding in Stamperenden accounted for 95.6%. The dominant species were Agapetus fuscipes, Lype reducta, Plectrocnemia conspersa, Potamophylax nigricornis and Silo pallipes.
- 3 The sex ratios in the catches of most species were uneven. Agapetus fuscipes males were in excess, probably because males fly more frequently than females.
- 4 The dominant species flew predominantly above the surface of the brook. Whereas both sexes of A. fuscipes, L. reducta and S. pallipes were rarely found even as little as 20–40m from the brook, the dispersal range of P. conspersa was much wider.
- 5 The implications of low dispersal for the biological recovery of damaged but subsequently restored streams and stream catchments are discussed. It is concluded that complete biological recovery may be a process requiring decades unless the original aquatic fauna is re-established artificially.
2.
Improved Coated Vesicle Isolation Allows Better Characterization of Clathrin Polypeptides 总被引:1,自引:0,他引:1
DEMMER ANNETTE; HOLSTEIN SUSANNE E. H.; HINZ GISELBERT; SCHAUERMANN GABRIELE; ROBINSON DAVID G. 《Journal of experimental botany》1993,44(1):23-33
Postmicrosomal pellets from plant sources are grossly contaminatedwith nbosomes. Previous purifications of clathrin coated vesicles(CCV) from such subcellular fractions have therefore often involvedan RNase treatment. Performed at 30°C, this step inherentlycarries with it the dangers of proteolysis. We document herea method for CCV isolation which avoids this. Through the inclusionof suitable antiproteases in the homogenizing and subsequentisolation media, we have also been able to improve the qualityof CCV recovered from plant tissues. As a result we have tentativelybeen able to identify clathrin light chains from zucchini hypocotyland pea cotyledon CCV. Similar to light chains from bovine brainthese polypeptides are heat stable, can be solubilized fromneutralized TCA precipitates, bind calcium and clathrin heavychains. However, in contrast to brain CCV the two light chainsof plant CCV are some 10 kDa heavier. Key words: Antiproteases, Ca2+-binding, clathrin coated vesicles, clathrin heavy chains, clathrin light chain(s), heat stability, pea cotyledons, RNase, zucchini hypocotyls 相似文献
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J. JONATHAN MOORE ANNETTE E. LITTLE 《Biological journal of the Linnean Society. Linnean Society of London》1994,51(1-2):253-256
The estuaries of the Taf, Tywi, Gwendraeth and Loughor (Carmarthen Bay, South Wales), and the Taw and Torridge (North Devon) were surveyed during the spring and summer of 1988, as part of a four year study of harbours, rias and estuaries in southern Britain commissioned by the Nature Conservancy Council. The aims of these surveys were to describe the major marine habitats and communities present in each estuary, and to assess their nature conservation importance. This paper outlines the results of these surveys, concentrating on the many environmental similarities between the six estuaries. 相似文献
4.
Comparative analysis of the grain proteome fraction in barley genotypes with contrasting salinity tolerance during germination 总被引:1,自引:0,他引:1
5.
Abstract: Shark teeth and scales from the Gneudna Formation type section, Carnarvon Basin are rare, but they represent a diverse fauna as well as being the first Frasnian chondrichthyan remains found in Western Australia. In contrast numerous shark teeth and scales have been obtained from coeval sections in the Canning Basin. Teeth referred to as Phoebodus bifurcatus, Phoebodus fastigatus, Phoebodus cf. fastigatus, Phoebodus latus , Phoebodus sp. C and Protacrodus sp. 1 are described from two Canning Basin localities: Horse Spring Range and McIntyre Knolls. The phoebodont species described here have a global distribution and can, therefore, be placed within the standard Frasnian phoebodont zonation. The shark remains from the Gneudna Formation type section include one new genus Emerikodus ektrapelus gen. et sp. nov., described along with Helodontidae indet and Elasmobranchii gen. et sp. indet. It is proposed that the faunal differences observed between the localities are a result of environmental differences. In addition to shark remains, scales from the thelodont Australolepis seddoni were also recovered from each locality. The well-dated Zone 6–10 conodont faunas at Horse Spring constrain the range of A. seddoni with which they occur, and importantly indicate that the Gneudna Formation type section is wholly Frasnian. 相似文献
6.
ESMATMOHAMEDHEGAZI ANNETTEHERZ SHERIFHASSAN ESSAMAGAMY WEDADKHAFAGI SANIASHWEIL AHMEDZAITUN SAFAAMOSTAFA MOHAMEDHAFEZ AHMEDEL-SHAZLY SOMAIAEL-SAID LAMIAABO-ABDALA NOHAKHAMIS SAMIAEL-KEMNY 《Insect Science》2005,12(3):185-192
A survey of two-year studies (2001-2003) was carried out in two olive groves sited at two representative olive growing areas, namely Paradise Park (arid area) and Burg E1-Arab farm (semi-arid area) to monitor the frequency of endemic Trichogramma species on olive moth (Prays oleae) and jasmine moth (Palpita unionalis). The suspended host bait traps were found to be a more practical and effective tool for collecting Trichogramma wasps than the attached ones. Four naturally occurring Trichogramma species were collected for the first time in Egypt from the olive groves, where releases have never been conducted. T.bourarachae was collected exclusively from Burg El-Arab farm. It seems that this wasp species adapts well to the semi-arid area. Three species, namely T. cordubensis, T. nr.pretiosum and T. cacociae were isolated from Paradise Park farm. All of these wasps were also bred from naturally parasitized host eggs during favorable and even at unfavorable temperature conditions of June-August. However, these endemic species did not occur naturally in sufficient numbers to keep the pest populations from reaching damaging levels.The excessive usage of insecticides and the oophagous predators (e.g., ants and lacewing larvae) are some factors that affect the performance of Trichogramma wasps in olive farms.The presence of warm weather wasp strains suggests the existence of well-adapted wasp species or swains which may be appropriate candidates for the control of target pests in olive groves. Additional study is required to determine the best “habitat-specific” species/strains of Trichogramma for augmentative release of naturally occurring wasps and to incorporate them into integrated pest management programs. Efforts should be made to conserve these endemic species from oophagous predators, hot weather and insecticides.The olive and jasmine moth-larvae and pupae found under tree canopies were bred and emerged parasitoids were listed. 相似文献
7.
Sodium iodate damages retinal pigment epithelium specifically, but the reason for this specificity is not well understood. The work reported here describes an effect of sodium iodate on melanin, a major component of the retinal pigment epithelium. Sodium iodate increases the ability of melanin to convert glycine to glyoxylate. Almost ten times as much glyoxylate is formed when sodium iodate is present compared to the amount formed with melanin alone, although iodate alone does not convert glycine to glyoxylate. A chemical reaction between sodium iodate and melanin is suggested as a partial explanation of the specificity of iodate toxicity towards retinal pigment epithelium. 相似文献
8.
Abstract. The genus Glaresis does not share any demonstrable apomorphs with any other group of Scarabaeoidea. Detailed examination of twelve adult characters and their comparison with those in all the primitive Scarabaeoidea resulted in a well-defined genus that is primitive in virtually all its characters. It is concluded that Glaresis lies near the base of the ancestral stock from which most scarabaeoids evolved. Since the genus cannot be accommodated in an existing higher taxon we propose that the monotypic tribe Glaresini Semenov & Medvedev (the genus Afroglaresis Petrovitz is here synonymized with Glaresis) , be accorded family status. 相似文献
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10.
ANNETTE GOMOT-DE VAUFLEURY RAPHAELLE BORGO 《Invertebrate reproduction & development.》2013,57(2-3):217-226
Summary The experimental laboratory pairing of hermaphroditic snails of different sub-species, Helix aspersa aspersa (H.a.a) and H. aspersa maxima (H.a.m.), made it possible to obtain both reciprocal hybrids for the first time and to describe their growth. The relatively small number of matings observed (20–25%) was partly responsible for the small number of clutches obtained (10–13%). The cross H.a.a.M × H.a.m.F is more fertile than the reciprocal. The observed tendency to reproductive isolation (behavioural and anatomical) suggests that H.a.a. and H.a.m. should be considered as two sub-species. Hybridization is not accompanied by a beneficial heterosis effect since significant juvenile mortality and an increased variation in growth were observed. The small size of H.a.a. is a dominant characteristic, whereas the colour of the mantle edge in the Fl individuals is intermediate between the black of H.a.m. and the white of H.a.a. The Fl generation is fertile and gives F2 snails with an adult size close to that of H.a.a. but slower growing. This approach allows investigations into the mechanisms underlying the reproductive isolation of parental sub-species. 相似文献