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  • Polymer and Materials Science  (101)
  • Physics  (12)
  • Lepidoptera  (6)
  • 1
    Digitale Medien
    Digitale Medien
    The responses of some Lepidoptera to labiate herb and white clover extracts (1985)
    Springer
    Entomologia experimentalis et applicata 39 (1985), S. 177-182 
    Details
    ISSN: 1570-7458
    Schlagwort(e): biological control ; brassica ; labiate herbs ; larval feeding ; oviposition ; Lepidoptera ; Pieris brassicae ; Plutella xylostella
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Beschreibung / Inhaltsverzeichnis: Résumé Des plantes médicinales ont traditionnellement été utilisées en association avec des plantes cultivées dans l'espoir que leur odeur repousserait les insectes nuisibles. Des extraits à l'alcool et des essences volatiles de labiées médicinales ont été essayés au laboratoire pour examiner leur effets répulsif et dissuadant pour la ponte de Plutella xylostella et l'alimentation des chenilles de P. xylostella et Pieris brassicae. Les extraits alcooliques d'hysope, de romarin, de sauge, de thym et de trèfle blanc réduisent la ponte de P. xylostella sur des morceaux de feuilles de chou traitées. Les essences volatiles de sauge et de thym réduisent la ponte de P. xylostella sur des morceaux de feuilles de chou dans des expériences de choix. L'alimentation des chenilles de dernier stade de P. xylostella et P. brassicae dans des expériences de choix est réduite par l'application d'extraits alcooliques des labiées médicinales.
    Notizen: Abstract Herbs have been traditionally used as intercrops with crop plants on the assumption that their odour repels pest species. Alcohol extracts and essential oils of labiate herbs were tested in the laboratory for deterrent/repellent responses to ovipositing Plutella xylostella (L.) and feeding larvae of P. xylostella and Pieris brassicae L. Alcohol extracts of hyssop, rosemary, sage, thyme and white clover reduce oviposition by P. xylostella on pieces of brassica leaf in dual-choice tests. Essential oils of sage and thyme reduce oviposition on pieces of brassica leaf. Feeding, in dual-choice tests, by final instar P. xylostella and P. brassicae larvae is reduced by application of alcohol extracts of herbs.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00414506
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  • 2
    Digitale Medien
    Digitale Medien
    Mapping and characterization of the entomocidal domain of the Bacillus thuringiensis CrylA(b) protoxin (1995)
    Springer
    Molecular genetics and genomics 247 (1995), S. 482-487 
    Details
    ISSN: 1617-4623
    Schlagwort(e): Bacillus thuringiensis ; Crystal protein ; Activation ; Lepidoptera ; Toxic fragment
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The amino acid sequences necessary for entomocidal activity of the CryIA(b) protoxin of Bacillus thuringiensis were determined. Introduction of stop codons behind codons Arg601, Phe604 or Ala607 showed that amino acid residues C-terminal to Ala607 are not required for insecticidal activity and that activation by midgut proteases takes place distal to Ala607. The two shortest polypeptides, deleted for part of the highly conserved β-strand, were prone to proteolytic degradation, explaining their lack of toxicity. Apparently, this β-strand is essential for folding of the molecule into a stable conformation. Proteolytic activation at the N-terminus was investigated by removing the first 28 codons, resulting in a translation product extending from amino acid 29 to 607. This protein appeared to be toxic not only to susceptible insect larvae such as Manduca sexta and Heliothis virescens, but also to Escherichia coli cells. An additional mutant, encoding only amino acid residues 29–429, encompassing the complete putative pore forming domain, but lacking a large part of the receptor-binding domain, was similarly toxic to E. coli cells. This suggests a role for the N-terminal 28 amino acids in rendering the toxin inactive in Bacillus thuringiensis, and indicates that the cytolytic potential of the pore forming domain is only realized after proteolytic removal of these residues by proteases in the insect gut. In line with this hypothesis are results obtained with a mutant protein in which Arg28 at the cleavage site was replaced by Asp. This substitution prevented the protein from being cleaved by trypsin in vitro, and reduced its toxicity to M. sexta larvae.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00293150
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  • 3
    Digitale Medien
    Digitale Medien
    Ecology of aquatic Lepidoptera (Crambidae: Nymphulinae) in South Carolina, USA (1998)
    Springer
    Hydrobiologia 379 (1998), S. 33-40 
    Details
    ISSN: 1573-5117
    Schlagwort(e): Lepidoptera ; Crambidae ; aquatic ecology ; aquatic plants ; distribution ; herbivory
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract An ecological study was conducted in May and June of 1995 and 1996 in South Carolina to determine the factors associated with distributions of aquatic Lepidoptera (Crambidae: Nymphulinae). Larvae were found at 65 lotic and lentic sites in three ecoregions (Piedmont, Sandhills, Coastal Plain). Nine species of aquatic Lepidoptera were collected from 12 species of aquatic vascular macrophytes. One to six plant species were used as hosts, depending on the species of lepidopteran; however, the number of host plants used by a lepidopteran was significantly correlated with the lepidopteran's frequency of occurrence. Significant habitat associations were found for five species. Langessa nomophilalis (Dyar) was found under the widest range of temperature and width and occurred in both lotic and lentic habitats. Munroessa icciusalis (Walker) was found in lotic and lentic habitats and had the widest range of recorded depths. Parapoynx maculalis (Clemens) occurred at stream sites with lentic-like conditions. Parapoynx obscuralis (Grote) occupied the widest range of pH and was restricted to lotic habitats, and P. seminealis (Walker) was found in both lotic and lentic habitats. Additional species, collected at fewer than 8% of sites, included M. gyralis, P. allionealis, Synclita obliteralis, and S. tinealis. Overall, the distributions of aquatic Lepidoptera in South Carolina were nonrandom and predictable on the basis of habitat characteristics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1003269025247
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  • 4
    Digitale Medien
    Digitale Medien
    Novel sex pheromone components from the fall cankerworm moth,Alsophila pometaria (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 463-473 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Alsophila pometaria (Harris) ; fall cankerworm ; Lepidoptera ; Geometridae ; sex pheromone ; (Z,Z,Z)-3,6,9-nonadecatriene ; (Z,Z,Z,E)-3,6,9,11-nonadecatetraene ; (Z,Z,Z,Z)-3,6,9,11-nonadecatetraene
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract A sex pheromone extract from fall cankerworm moths,Alsophila pometaria, attracted conspecific males in field tests. Four EAG-active components were isolated from the extract and identified by GC-MS, highfield PMR spectroscopy, and microchemical techniques asn-nonadecane (I), (Z,Z,Z)-3,6,9-nonadecatriene (II), (Z,Z,Z,E)-3,6,9,11-nonadecatetraene (III), and (Z,Z,Z,Z)-3,6,9,11-nonadecatetrane (IV). Studies of the behavioral responses of male moths in a flight tunnel to the isolated components showed II, III, and IV were the major components of the sex pheromone. No sex pheromone behavioral responses were observed for I.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00988092
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  • 5
    Digitale Medien
    Digitale Medien
    Multiple denaturational transitions in fibrillar collagen (1986)
    New York : Wiley-Blackwell
    Biopolymers 25 (1986), S. 1875-1893 
    Details
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The heat denaturation of pepsinized bovine nonfibrillar and fibrillar collagen was studied by differential scanning calorimetry. For fibrillar preparations that had been rapidly precipitated with stirring at low ionic strength, then resuspended at physiological ionic strength, multiple denaturational transitions were observed. At heating rates of 10°C/min, melting endotherms occurred at about 44, 50, 53, and 57°C. Fibrillar collagen that was slowly gelled without stirring at physiological ionic strength exhibited a similar series of endotherms, but the lower melting transitions were less conspicuous. In contrast, nonfibrillar bovine collagen in acidic solution showed only a single denaturational transition at 40°C. Nonfibrillar solutions at pH 7, to which inhibitors of fibrillogenesis were added, showed a major endotherm as high as 46°C. These results suggest that reconstituted fibrillar collagen contains a heterogeneous fibril population, possibly including molecules in a nonfibrillar state. It was proposed that the multiple melting endotherms of such preparations were due to sequential melting of molecular and fibril classes, each with a distinct melting temperature. The fibrillar classes may represent three or more types of banded and nonbanded species that differ from each other in packing order, collagen concentration, and possibly also in fibril width and level of cross-linking.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bip.360251006
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  • 6
    Digitale Medien
    Digitale Medien
    Effects of pH and temperature on cardioactive polypeptides from sea anemones: A 1H-nmr study (1988)
    New York : Wiley-Blackwell
    Biopolymers 27 (1988), S. 1143-1157 
    Details
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The effects of pH and temperature on the 300-MHz 1H-nmr spectra of three cardioactive polypeptides from sea anemones, anthopleurin-A from Anthopleura xanthogrammica (AP-A) and Anemonia sulcata toxins I and II (ATX I and II), are described. AP-A and ATX II exhibit major spectral heterogeneity. Evidence from the pH and temperature studies and from high performance liquid chromatography indicates that this heterogeneity is conformational rather than chemical in origin. By contrast, purified isotoxins of ATX I show no evidence of conformational heterogeneity. The pKa values of most of the ionizable groups in these polypeptides are not strongly perturbed by interactions in the tertiary structure, with the exception of one of the Asp carboxylates, which has a pKa of ≲ 2 in AP-A and ATX II and 3.0 in ATX I. Protonation of this carboxylate, suggested to be Asp-9, leads to a conformational change in all three molecules. All three polypeptides are thermally stable, showing some conformational changes but not major unfolding at elevated temperatures.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bip.360270708
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  • 7
    Digitale Medien
    Digitale Medien
    7-Amino-actinomycin D complexes with deoxynucleotides as models for the binding of the drug to DNA (1979)
    New York : Wiley-Blackwell
    Biopolymers 18 (1979), S. 1749-1762 
    Details
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Fluorescence, CD, absorption, and 1H-nmr studies are reported for complexes of 7-amino-actinomycin D with deoxydinucleotides, deoxytetranucleotides, and poly(dG-dC)· poly(dG-dC). The optical spectra for the 7-amino-actinomycin D complex with pdG-dC, pdG-dC-dG-dC and pdC-dG-dC-dG are similar in shape to the 7-amino-actinomycin D complex with either DNA or poly(dG-dC). The changes in the 1H chemical shifts of the 7-amino-actinomycin D and the pdG-dC resonances that accompany complex formation show that 7-amino-actinomycin D forms a minature intercalated complex with two pdG-dC molecules. The magnitudes of the induced chemical shifts for the 7-amino-actinomycin D complex formation with pdG-dC are similar to, but slightly different from, the induced chemical shifts which are obtained when actinomycin D forms a minature intercalated complex with two pdG-dC molecules. The pdN-dG dinucleotides (N = C, A, or T) form stacked complexes with 7-amino-actinomycin D. The presence of the 7-amino-group results in a larger dimerization constant (in aqueous solution) for 7-amino-actinomycin D [KD(6°C) = 4.4 × 103M-1], as compared to actinomycin D [KD(6°C) = 1.7 × 103M-1]; the chemical shifts which accompany dimer formation indicate that the chromophores stack in an inverted manner. Intercalation of 7-amino-actinomycin D into minature double helices, as well as into calf thymus DNA, poly(dG-dC)·poly(dG-dC), and poly(dA-dC)·poly(dG-dT), results in an enhancement of the relative fluorescence intensity and a shift in both the absorbance and corrected emission spectra.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bip.1979.360180712
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  • 8
    Digitale Medien
    Digitale Medien
    Molecular dynamics simulations of a winter flounder “antifreeze” polypeptide in aqueous solution (1993)
    New York : Wiley-Blackwell
    Biopolymers 33 (1993), S. 1481-1503 
    Details
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: A winter flounder antifreeze polypeptide (HPLC-6) has been studied in vacuo and in aqueous solution using molecular dynamics computer simulation techniques. The helical conformation of this polypeptide was found to be stable both in vacuum and in solution. The major stabilizing interactions were found to be the main-chain hydrogen bonds, a salt-bridge interaction, and solute-solvent hydrogen bonds. A significant bending in the middle of the polypeptide chain was observed both in vacuo and in solvent at 300 K. Possible causes of the bending are discussed. From simulations of mutant polypeptide molecules in vacuo, it is concluded that the bend in the native polypeptide was caused by side chain to backbone hydrogen bond competition involving the Thr 24 side chain and facilitated by strains on the helix resulting from the Lys 18-Glu 22 salt bridge. © 1993 John Wiley & Sons, Inc.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bip.360331002
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  • 9
    Digitale Medien
    Digitale Medien
    A small-angle x-ray scattering study of alginate solution and its Sol-Gel transition by addition of divalent cations (1995)
    New York : Wiley-Blackwell
    Biopolymers 35 (1995), S. 227-238 
    Details
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: The small-angle x-ray scattering (SAXS) technique has been applied to investigate solution and gel structures of alginate in the absence and presence of two divalent cations: Ca(II) and Cu(II). We have observed a broad maximum in the scattering curve, a characteristic of polyelectrolyte, for the purified alginate sample. The scattering maximum disappears in excess of added simple salt and shifts toward the higher angle region with increasing alginate concentration. Concentration dependence of the position and intensity of the maximum follows power law relations with exponents close to those predicted by theory. Data analysis shows an increase in correlation length ξ and cross-sectional diameter d0, of polymer chains upon gelation and suggests that a dimeric structure is adopted in the junction zone, consistent with the “egg-box” model previously proposed. In the Ca(II)-alginate system, the molecular parameters ξ and d0 are found to have good correlation with the macroscopic properties of gelation, such as gel point determined by viscosity measurements. However, for the Cu(II)-alginate system there is no clearly transitional behavior observed in ξ and d0, implying that the junction zone may be replaced by a more uniformly distributed site binding of Cu(II) ions to the carboxyl groups of both mannuronate and guluronate residues, in confirmation of previous 13C-nmr results. © 1995 John Wiley & Sons, Inc.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/bip.360350211
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  • 10
    Digitale Medien
    Digitale Medien
    Bis[4(1-methyl-1,2-epoxyethyl)] derivatives of phenyl ether, 1,4-diphenoxybenzene, and bis(4-phenoxyphenyl) etherProd. No. 1615 (1967)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 2029-2036 
    Details
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The syntheses of three new α-methyl-substituted bis(epoxyethyl) derivatives of phenyl ether, 1,4-diphenoxybenzene, and bis(4-phenoxyphenyl) ether are reported. Improved procedures for preparing 1,4-diphenoxybenzene and bis(4-phenoxyphenyl) ether by the Ullmann method are described. Infrared spectral data for the bisepoxides and their precursors are given, as are some reactions of the bisepoxides.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/app.1967.070111019
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