ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Immunocytochemistry  (70)
  • 42.55  (47)
  • Drosophila  (47)
  • Coleoptera  (44)
  • Springer  (208)
  • Annual Reviews
  • Blackwell Publishing Ltd
  • Massachusetts Institute of Technology and Woods Hole Oceanographic Institution
  • 2020-2024
  • 2005-2009
  • 1980-1984  (208)
  • 2009
  • 1984  (109)
  • 1982  (99)
Sammlung
Schlagwörter
Verlag/Herausgeber
Erscheinungszeitraum
  • 2020-2024
  • 2005-2009
  • 1980-1984  (208)
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    Pitfall-trap catches of the carabid beetle Pterostichus melanarius, in relation to gut contents and prey densities, in insecticide treated and untreated spring barley (1984)
    Springer
    Entomologia experimentalis et applicata 36 (1984), S. 23-30 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Pterostichus melanarius ; Coleoptera ; Carabidae ; pitfall traps ; insecticides ; prey ; hunger ; activity ; Rhopalosiphum padi ; Fenitrothion ; Sumicidin (Fenvalerate) ; spring barley
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Beschreibung / Inhaltsverzeichnis: Résumé Au cours d'essais à grande échelle, effectués en 1981 et 1982, sur orge de printemps, pour évaleur l'effet des insecticides Fenitrothion et Sumicidine (fenvalerate) sur les arthropodes utiles, un accroissement significatif des captures, dans des trappes pièges de Barber, de Pterostichus melanarius (Illiger) a été observé plusierus semaines après le traitement dans les lots traités par rapport aux lots témoins. Significativement plus de femelles de P. melanarius ont été capturées dans les parcelles traitées pendant cette période d'accroissement après traitement. Une diminution correspondante dans les populations de proies a été observée à la suite des traitements. Chaque femelle de P. melanarius des parcelles traitées avait une fraction significativement moins importance de son intestin remplie d'aliments solides (arthropodes) que celles des parcelles non traitées. Des auteurs précédents avaient observé des taux de capture plus rapides dans les trappes et ne plus grande mobilité des carabes affamés. La réduction des populations proies par l'application d'insecticides affamerait les carabes dont l'activité serait par suite plus élevée. Comme le taux de captures dans les trappes est dû à la fois à la taille de la population et à son activité, on en déduit que la capture par trappes seule ne peut donner une image exacte de l'effet des insecticides sur les populations de carabes dans les champs.
    Notizen: Abstract During large-scale field experiments in 1981 and 1982, designed to assess the effects of the insecticides Fenitrothion and Sumicidin (Fenvalerate) on beneficial arthropods in spring barley, significant increases in pitfall-trap catches of Pterostichus melanarius (Illiger) were observed in treated plots compared to untreated controls, several weeks after treatment. Significantly more female P. melanarius were caught in treated plots during these post-treatment increases. Corresponding decreases were observed in prey populations following treatments. Individual female P. melanarius from treated plots had significantly fewer of their gut areas full of solid (arthropod) food when compared to those from untreated control plots. Earlier workers observed both faster recapture rates in pitfalls and higher mobility in hungry carabid beetles. The following hypothesis is suggested: reducing prey populations by the application of insecticides results in hungrier carabid beetles with consequently higher activity. Since pitfall-trap catch is determined not only by population size but also activity, it is argued that pitfall-trap catches alone cannot give a true measure of the effects of insecticides on carabid populations in the field.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00345200
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Distribution of proteinases and carbohydrases in the midgut of larvae of the sweetpotato weevilCylas formicarius elegantulus and response of proteinases to inhibitors from sweet potato (1984)
    Springer
    Entomologia experimentalis et applicata 36 (1984), S. 97-105 
    Details
    ISSN: 1570-7458
    Schlagwort(e): Coleoptera ; Curculionidae ; Cylas formicarius elegantulus ; sweetpotato weevil ; sweet potato ; digestion ; enzyme distribution ; trypsin-inhibitors ; resistance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Beschreibung / Inhaltsverzeichnis: Résumé L'activité endoprotéinase était limitée au liquide de la lumière des régions ventriculaires antérieure et postérieure de l'intestin moyen des larves deCylas formicarius elegantulus Summers. Les aminopeptidases ont été trouvées dans le liquide de la lumière (18%), mais étaient principalement associées avec les fractions insolubles des cellules du ventricule postérieur (82%). Suivant le substrat, l'activité carboxypeptidase était à peu près également répartie entre le liquide de la lumière et les fractions insolubles des cellules du ventricule postérieur. L'amylase, enzyme secrétée, a été observée à la fois dans la lumière antérieure et postérieure. Cinq bandes d'activité amylase ont été révélées sur zymogrammes d'amidon après électrophorèse d'intestins moyens entiers. Trois des bandes d'amylase pouvaient provenir de la plante. Il y avait au moins 2 α-glucosidases, une secrétée et une liée aux cellules du ventricule antérieur. L'activite β-glucosidase était liée aux cellules du ventricule antérieur, fandis que l'activité α-galactosidase était limitée au fluide de la lumière. Les activités β-galactosidase et cellulase ont été trouvées à la fois dans le liquide de la lumière et dans la fraction cellulaire insoluble. Ainsi, la digestion initiale des grosses protéines et des polymères de carbohydrates se produit dans le liquide de la lumière dans les régions ventriculaires antérieure et postérieure. Cependant, l'achèvement de la digestion des oligopeptides se produit principalement dans le ventricule postérieur, tandis que la fin de la digestion des oligosaccharides se produit dans le ventricule antérieur. Les concentrations en inhibiteurs de trypsine de 5 cultivars d'I. batatas L. diffèrent de 1 à 20. Les endoprotéinases deC. formicarius elegantulus ont été inhibées par des extraits de cultivars, mais les cultivars avec des concentrations relativement élevées d'inhibiteur avainent antérieurement montré être susceptibles d'être attaqués par le coléoptère dans des essais en champs.
    Notizen: Abstract Endoproteinase activity was confined to luminal fluid from anterior and posterior ventricular regions of midguts of larvae of the sweetpotato weevil,Cylas formicarius elegantulus (Summers). Aminopeptidase was found in luminal fluid (18%) but was primarily associated with insoluble fractions from cells of the posterior ventriculus (82%). Depending on substrate, carboxypeptidase activity was about equally distributed between luminal fluid and insoluble fractions from posterior ventriculus cells. Amylase was found in luminal fluid in both the anterior and posterior ventriculus. Five bands of amylase activity were detected on starch zymograms following electrophoresis of whole midgut samples. Three of the amylase bands may be plant-derived. At least two α-glucosidases were present, one secreted and one bound to anterior ventriculus cells. β-Glucosidase activity was bound to anterior ventriculus cells whereas α-galactosidase activity was confined to luminal fluid. β-Galactosidase and cellulase activities were found in both luminal fluid and the insoluble cell fraction. Thus, initial digestion of large protein and carbohydrate polymers occurs in luminal fluid in both anterior and posterior ventriculus regions. However, terminal digestion of oligopeptides occurs primarily in the posterior ventriculus while terminal digestion of oligosaccharides occurs in the anterior ventriculus. A 20-fold difference in trypsin-inhibitor concentration was found among five sweetpotato cultivars. Endoproteinases from sweetpotato weevil larvae were inhibited by extracts from the cultivars but cultivars with relatively high concentrations of inhibitor were previously shown to be susceptible to weevil attack in field trials.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00569949
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Group theory and experiments on helical and linear distributed feedback gas lasers (1984)
    Springer
    Applied physics 33 (1984), S. 115-131 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 02.20 ; 42.55 ; 42.60D
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract This study puts forward the concept of helical distributed feedback (DFB) lasers. The basic features of this new type of laser are derived by group theoretical considerations on cylindrical, circular linear periodic, and helical waveguide and laser structures. It is demonstrated that not only linear periodic structures but also helical structures show Bragg and DFB effects. Microwave and far-infrared experiments on passive helical metal waveguides reveal Bragg resonances in transmission. These results initiated the first experimental realization of a helical DFB gas laser, i.e. an optically pumped 496μm CH3F laser with a helical metal waveguide of a pitch close to 250μm. This helical DFB laser shows higher-mode selectivity than the corresponding linear DFB laser. Finally, we show that the concept of helical DFB also applies to dye lasers with internal DFB incorporated by a mixture of the dye with a cholesteric liquid crystal.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688518
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Submillimetre laser lines from CH3OH pumped by a13C18O2 pump laser: Observations and assignments (1984)
    Springer
    Applied physics 34 (1984), S. 17-21 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Twenty-four new optically pumped submillimetre laser lines have been observed when CH3OH is excited using a13C18O2 pump laser. Four of these lines have been assigned to transitions involving the CO stretching band. In addition to these lines, a further six new lines have been observed when pumping with12C18O2 and13C16O2 lasers. One of these lines has been assigned to a transition involving the CO stretching band. The observation of infrared-infrared double resonance signals in CH3OH has allowed the prediction of a further six laser lines which should be excited using a13C18O2 pump laser.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697459
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Coherent effects in inverse compton scattering in the high frequency region (1984)
    Springer
    Applied physics 34 (1984), S. 221-228 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 41
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The conditions under which a cooperative emission from different friges occurs in the scattering between a relativistic electron beam and two interfering laser beams are discussed. In particular, the conditions to have an electron grating are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697638
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Bistability and passive Q-switching of a CO2 laser with saturable absorber (1984)
    Springer
    Applied physics 35 (1984), S. 77-82 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.65
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The coexistence of bistability and repetitive passive Q-switching of a CO2 laser with a gaseous saturable absorber has been investigated experimentally. With CH3F as the saturable absorber bistability has been observed simultaneously with passive Q-switching, whereas with CH3OH either one of these phenomena can only exist, as demonstrated for the first time. The measured features of both systems can be explained qualitatively by rate-equation theory.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697426
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Optically pumped submillimetre laser action in formaldoxime and ammonia (1984)
    Springer
    Applied physics 35 (1984), S. 127-129 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Strong submillimetre laser action has been obtained on five lines of a new laser gas, formaldoxime. Several new emission lines have also been produced by isotopic CO2 laser pumping of14NH3 and15NH3. One of these lines at 102.9 μm is a rotation-inversion transition in the 2v 2 state, and is the first example of cw laser action in such a highly excited state.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697700
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Stepwise photoionization of complex organic molecules in the gas phase induced by UV laser radiation (1982)
    Springer
    Applied physics 27 (1982), S. 57-61 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 33 ; 82.50 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract We measured the photoionization cross-sections of anthracene, 1,2-benzanthracene,p-terphenyl, and 2,5-diphenylfuran molecules excited to the singlet and triplet electronic states intermediate in the stepwise two-photon ionization process at 266 nm (all compounds) and at 355, 391 and 417 nm (anthracene).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697297
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Origin of laser-output noise of cataphoretic HeSe+ lasers (1982)
    Springer
    Applied physics 28 (1982), S. 373-381 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.80 ; 52
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract We investigated noise and fluctuations of the output power of cataphoretic HeSe+ lasers in positive column plasma. Direct coupling of laser output power noise and fluctuations of the local population inversion was found. An investigation of the positive column plasma showed moving striations being responsible for the gain fluctuations. Whereas the local plasma properties are dominated by high frequency striations in the 100 kHz range, integrated quantities such as laser gain per pass are most strongly influenced by low-frequency waves with a continuous noise spectrum below 200 kHz. External modulation of the discharge voltage or current at a frequency near thehf striations reduces laser noise and increases laser output power.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00686369
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    Lifetime, photostability, and chemical structure of IR heptamethine cyanine dyes absorbing beyond 1 μm (1982)
    Springer
    Applied physics 29 (1982), S. 15-18 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 32 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Optical absorption,S 1 lifetime, and photostability are investigated for a series of heptamethine ir dyes and related to chemical structure. The high photostability of several dyes and the large range ofS 1 lifetimes make these dyes very interesting for ir dye lasers and for ir mode-locked laser systems.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00694363
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 11
    Digitale Medien
    Digitale Medien
    Strong far-infrared laser action in carbonyl fluoride and vinyl fluoride (1982)
    Springer
    Applied physics 29 (1982), S. 13-14 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Intense far-infrared laser action is reported for carbonyl fluoride and vinyl fluoride. Eleven new lines with wavelengths between 339 μm≦λ≦538 μm were obtained by optically pumping carbonyl fluoride with numerous lines of the 10.4 μm band of a cw CO2 laser. Twenty-three lines with wavelengths in the range 172 μm≦λ≦783 μm were detected when pumping the recently discovered efficient FIR laser molecule vinyl fluoride. In addition, three very weak new lines were found using 1.1-difluoroethylen.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00694362
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 12
    Digitale Medien
    Digitale Medien
    Temporal analysis of a mode-locked Nd-glass laser by four-wave mixing (1982)
    Springer
    Applied physics 29 (1982), S. 263-267 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.65 ; 42.80
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The duration, shape, and background intensity level of pulses of a passively modelocked Nd-glass laser are determined by noncollinear phase-matched four-photon frequency mixing of time-separated fundamental and second-harmonic pulses in a KI crystal. The pulse shape is found to be slightly asymmetric with slower trailing than rising parts. The background intensity level before and behind the main pulse is about 5¢10−6 the peak pulse intensity.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00689185
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 13
    Digitale Medien
    Digitale Medien
    CW and pulsed FIR-CO2 hybrid laser with improved efficiency and amplitude stability at short FIR wavelengths (1984)
    Springer
    Applied physics 33 (1984), S. 23-27 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract For the first time stable cw output of a FIR-CO2 hybrid laser has been achieved at wavelengths shorter than 300 μm. Due to the saturable absorber characteristic of the FIR laser gas, cw or pulsed emission is observed on both, the CO2 and the FIR laser output, depending on the operating conditions. Results are reported on different resonant lines in CH3OH and the 67 μm Raman line in NH3. The good efficiency of this laser is also demonstrated by the excitation of two new emission lines in CH3OH, namely 49 and 56 μm, pumped by 9R(22) and 9R(24), respectively.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00690022
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 14
    Digitale Medien
    Digitale Medien
    The effect of triplet quenchers on vapor-phase dye-laser performance (1984)
    Springer
    Applied physics 34 (1984), S. 83-86 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 33.50 ; 34.50 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract An XeF pumped vapor phase POPOP dye laser with a pulse duration of 300 ns was obtained when trans-stilbene was used as triplet quencher. An energy conversion efficiency of 7,5% with a peak power efficiency of 12% was measured.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697952
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 15
    Digitale Medien
    Digitale Medien
    New cw fir laser emissions from CO2 laser-pumped vinyl bromide (1984)
    Springer
    Applied physics 34 (1984), S. 175-177 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract 47 new cw far-infrared laser lines with wavelenths between 453 and 2356 μm have been obtained by optically pumping vinyl bromide (C2H3Br) by a CO2 laser. A significant portion of these lines has wavelengths longer than 750 μm.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697631
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 16
    Digitale Medien
    Digitale Medien
    Small-signal gain of Free Electron Laser in a resonator Gaussian mode (1984)
    Springer
    Applied physics 35 (1984), S. 163-166 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.50 ; 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract We present an analytical expression for the small-signal gain of a Free Electron Laser (FEL) in the presence of a Gaussian mode. To describe the electron beam evolution we use the one-dimensional (1-d) Vlasov equation. Our perturbation result, valid for small values of the parameterq (length of the undulatorL divided by the Rayleigh rangeZ R), can be extrapolated to values ofq≈4÷5.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697707
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 17
    Digitale Medien
    Digitale Medien
    Transverse mode dynamics in a free-electron laser (1984)
    Springer
    Applied physics 33 (1984), S. 9-16 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.60 ; 42.20 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract We derive the most general equations of motion for the electrons and the electromagnetic field in a free-electron laser including the effects of diffraction and pulse propagation. The field evolution is expressed in terms of the amplitudes and phases of a complete set of transverse modes. The analytic solution is given in the small-signal regime, where the theory is shown to be in excellent agreement with a recent experiment at Orsay.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00690020
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 18
    Digitale Medien
    Digitale Medien
    Pressure dependence of laser oscillation and superfluorescent emission from an optically pumped CF4 laser (1984)
    Springer
    Applied physics 34 (1984), S. 37-41 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Experiments on pressure dependence of a CF4 laser have been carried out to elucidate dynamic characteristics of CF4 molecules pumped by CO2 lasers. The results are followed by a model calculation which characterizes collisional quenching of the energy levels related to the stimulated emission. The enhancement of the laser output induced by buffer-gas addition, which was found under specific conditions, is discussed in relation to the competition between laser and superfluorescent emissions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697463
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 19
    Digitale Medien
    Digitale Medien
    Free electron laser (1982)
    Springer
    Applied physics 28 (1982), S. 150-154 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697840
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 20
    Digitale Medien
    Digitale Medien
    Surface spectroscopy (1982)
    Springer
    Applied physics 28 (1982), S. 229-232 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 82.65 ; 68 ; 36.40 ; 78 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697849
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 21
    Digitale Medien
    Digitale Medien
    Guided waves and IR lasers (1982)
    Springer
    Applied physics 28 (1982), S. 283-289 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 85.60 ; 42.80 ; 42.55 ; 33
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697857
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 22
    Digitale Medien
    Digitale Medien
    Intense laser generation from an atomic-fluorine laser (1984)
    Springer
    Applied physics 33 (1984), S. 235-238 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract An intensive generation of radiation from a discharge-pumped atomic-fluorine gas laser is reported. A peak power exceeding 330 kW and a total energy of more than 2 mJ is obtained for a number of lines in the red, using a NF3∶He (1∶100) gas mixture at total pressure of 500 Torr. The circuitry optimization is described and the conditions for effective operation of the atomic-fluorine laser are discussed. The temporal and the spectral characteristics of the laser emission are also presented.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697333
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 23
    Digitale Medien
    Digitale Medien
    Free electron laser (1982)
    Springer
    Applied physics 29 (1982), S. 157-158 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.60 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688657
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 24
    Digitale Medien
    Digitale Medien
    New lasers and laser schemes (1982)
    Springer
    Applied physics 29 (1982), S. 143-148 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.60 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Conclusion We have demonstrated the existence of an anomalous polarization coupling mechanism present in the injection locked TEA CO2 laser. As a direct consequence of this work, a new injection technique has been formulated which permits efficient injection coupling and maximises energy extraction whilst eliminating the detrimental optical feedback effects to which other injection locking systems are prone.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688654
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 25
    Digitale Medien
    Digitale Medien
    Energy transfer in slab dye lasers (1984)
    Springer
    Applied physics 35 (1984), S. 71-75 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.60 ; 42.55 ; 42.72
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract A simple model of the energy transfer between a booster dye and the active dye in a flashlamp pumped planar waveguide dye laser is described. Analytical results are compared with experiments for several dyes in the 600–650 nm region. A twofold increase of laser output was found at a wavelength (630 nm) which is of particular interest for several applications.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697425
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 26
    Digitale Medien
    Digitale Medien
    Self-phase locking in lasers with homogeneously broadened emission lines (1984)
    Springer
    Applied physics 33 (1984), S. 187-193 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.50 ; 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract It is shown by numerical analysis based on Lamb's equations of motion, that standing-wave lasers with purely homogeneously broadened emission lines exhibit regular multimode oscillations. Specifically, modes lying far from the line centre are quenched due to mode competition, and the amplitudes of the oscillating modes approach steady-state values. The stabilization of the amplitudes is normally accompanied, or followed, by an evolution of the phases towards a phase-locked regime, where the relative phasesψ n = 2φ n −φ n + 1 −φ n − 1 [φ n phase in then th mode, defined by (6)] attain either the value 0 or ± π. The build-up times for the relative phases are found to vary over a wide range.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688527
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 27
    Digitale Medien
    Digitale Medien
    Improved gain on the Cl2(D′3 П g −A′3 П u ) transition at 258 nm by halogen donor mixing (1984)
    Springer
    Applied physics 35 (1984), S. 11-15 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The temporal development of the small-signal gain on the Cl2(D′−A′) transition at 258 nm has been investigated by means of an amplified spontaneous emission (ASE) technique. For electron beam pumped He/Cl2 mixtures, the gain appears only at the end of the pumping pulse, whereas for He/Cl2/CCl4 mixtures the temporal gain profile coincides with the fluorescence pulse, and the maximum gain coefficient increases by about a factor of two. The observed effects are due to the mixing of both halogen donors and can be explained by considering the quenching of theD′-state by electrons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697515
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 28
    Digitale Medien
    Digitale Medien
    Theory of the synchronously pumped picosecond dye laser (1982)
    Springer
    Applied physics 27 (1982), S. 27-37 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The circulation of a synchronously mode locked dye laser pulse in a linear cavity configuration containing a dye cell as an active medium and a bandwidth-limiting element is treated. The condition that the pulse shape reproduces after each cavity round-trip provides a nonlinear integro-differential equation for the steady-state pulse shape. For the solution of this equation an approximate method, not limited to small pulse energies, is given and the pulse duration, intensity, energy, asymmetry of the pulse shape, stable regions and other interesting parameters are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697293
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 29
    Digitale Medien
    Digitale Medien
    The He/Cl2 laser at 258 nm (1982)
    Springer
    Applied physics 27 (1982), S. 49-55 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 34 ; 33
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Lasing from e-beam pumped He/Cl2 mixtures at 258 nm was investigated in a longitudinal pumping geometry. Time dependence, output powers and energies as well as the spectral composition of the laser pulses were determined for different experimental conditions. Optical gain was observed for eight transitions around 258 nm. The fine structure results from isotopic splitting and contributions from different vibrational states. No bottle-necking occurs. However, saturation and absorption by excited states limited the total output power to 6MW and the output energies to 200 mJ. A simple kinetic model is proposed that reproduces the larger number of experimental data quite sufficiently.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697296
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 30
    Digitale Medien
    Digitale Medien
    Ultra-violet excited laser emission in Na2 (1982)
    Springer
    Applied physics 29 (1982), S. 195-200 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 35
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Laser emission at different wavelengths in the range of 903–914 nm and around 2.5 μm has been observed upon excitation of Na2 by uv radiation from an excimer laser at 351 nm and an excimer pumped dye laser in this wavelength range. The emission is attributed to a cascade emission $$C^1 \Pi _u \to 2^1 \sum _g^ + $$ followed by $$2^1 \sum _g^ + \to A^1 \sum _u^ + $$ . In addition, coupled with the laser emission around 910 nm, broad-band fluorescence peaking around 855.5 nm is observed which, eventually, may be the first observation of the $$b^3 \sum _g^ + \to x^3 \sum _u^ + $$ bound-free transition in Na2.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688667
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 31
    Digitale Medien
    Digitale Medien
    Theory of passively mode-locked cw dye lasers (1982)
    Springer
    Applied physics 27 (1982), S. 105-113 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The circulation of an ultrashort light pulse in a continuously pumped modelocked dye laser with a linear cavity configuration containing the active dye, the saturable absorber and a bandwidth-limiting elements is treated. The steady-state condition that the pulse shape reproduces after each cavity round-trip leads to a nonlinear integro-differential equation for this pulse shape. An approximate method for the solution of this equation not limited to the case of low laser gain and small pulse energies is given. The stable single pulse region and characteristic pulse parameters, as energy, duration, intensity and asymmetry, are considered in dependence on the laser parameters.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697557
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 32
    Digitale Medien
    Digitale Medien
    On the theory of electron motion due to superposed em waves and its application to the free-electron laser with linear polarization (1982)
    Springer
    Applied physics 28 (1982), S. 15-20 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 41
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The relativistic motion of a charged particle in an electromagnetic field depending only on one coordinate is shown to be exactly equivalent to the unidimensional motion of a particle having a time and space-varying mass. By means of the averaged Lagrangian method an approximate solution is obtained for the relativistic electron motion in two oppositely moving waves of any polarization, one of them being weaker than the other one, thus generalizing the results previously obtained for circular polarization. A comparison with numerical calculations shows a good agreement. A pendulum-like motion in an effective periodic potential is shown to exist not only for two waves of the same frequency, but more generally when the frequency of the weaker wave is an odd harmonic of the frequency of the stronger one.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00693886
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 33
    Digitale Medien
    Digitale Medien
    A subpicosecond dye laser pumped by a xenon ion laser (1984)
    Springer
    Applied physics 34 (1984), S. 191-192 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract A pulsed xenon ion laser has been used to pump a rhodamine 6G dye laser utilizing a ring resonator. The dye laser has been passively mode-locked; a pulsewidth of 0.5 ps and a 50 kW peak power have been obtained.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697634
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 34
    Digitale Medien
    Digitale Medien
    Novel quantum-electronics phenomena and devices (1982)
    Springer
    Applied physics 29 (1982), S. 152-156 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.80 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00688656
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 35
    Digitale Medien
    Digitale Medien
    Electron dynamics in free electron laser resonator modes (1982)
    Springer
    Applied physics 29 (1982), S. 101-109 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.50 ; 42.55 ; 52.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract We study the electron phase-space evolution and gain in free electron lasers whose short-wavelength radiation has Gaussian spherial wavefronts. Several free electron laser designs are considered: the undulator, the tapered wavelength undulator, and the optical klystron. We find that the gain spectrum is no longer proportional to the slope of the forward spontaneous emission spectrum, and we determine the design of the Gaussian mode which maximizes the energy extraction from the electron beam.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00692771
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 36
    Digitale Medien
    Digitale Medien
    A new blue-green XeF (C→A) excimer laser amplifier concept (1984)
    Springer
    Applied physics 35 (1984), S. 227-231 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The feasibility of using the electrically excited XeF(C»A) excimer medium as an efficient wideband amplifier in the blue-green region of the spectrum has been investigated. Calculations show that for an intense blue-green optical flux input the amplification characteristics of XeF(C»A) improve, as a result of both bleaching of the pump induced absorbers and by additional production of XeF(C) level population. The removal of one of the major absorbing species, Xe** in the XeF (C»A) laser mixture by means of a pulsed ruby laser probe beam has been demonstrated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00693931
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 37
    Digitale Medien
    Digitale Medien
    Waveguide CW 118.6 μm H2O laser (1982)
    Springer
    Applied physics 27 (1982), S. 123-128 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 42.60
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract This paper reports results of an experimental study of a cw 118.6 μm H2O waveguide laser. The laser cavity is a 3 cm inner diameter, 3.2 m long Pyrex tube, with plane reflectors against its ends, one of them being a copper mesh coupler. The active medium is a H2O:H2 gas mixture. Successive optimizations lead to a reliable output power of 50 mW, for the EH11 mode. The power density is the highest ever reported, and the stability is such that the power drifts by less than 2% per hour. This laser is competitive with the optically pumped 118.8 μm CH3OH laser.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00694636
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 38
    Digitale Medien
    Digitale Medien
    Picosecond pulse transmission in germanium of various thicknesses (1982)
    Springer
    Applied physics 27 (1982), S. 201-205 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.10 ; 42.55 ; 78.20
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The transmission of ultrashort pulses from a mode-locked Nd: glass laser in germanium of various thicknesses (3 to 8 μm) has been measured as a function of incident irradiance. Transmission is seen to increase with irradiance level in all samples. The degree of enhancement is greater for the thcker samples. At high excitation levels, thinner samples show a peaking of transmission, which does not occur in a thick sample. Taking the sample as composed of thin elements, the parameters characterizing the photoexcited electron-hole plasma have been found by assuming homogeneous excitation within each element. Theoretical curves thus obtained give good quantitative account of the experimental results. Peaking of transmission is seen to due to a balance between absorption enhancement in the front portion of the sample and absorption reduction in the back.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697442
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 39
    Digitale Medien
    Digitale Medien
    Optically pumped14NH3 laser and its stark tuning at 10.78 μm (1982)
    Springer
    Applied physics 28 (1982), S. 55-62 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 33 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Infrared (ir) emissions from a TEA-CO2-laser-pumped NH3 laser are reported. Superfluorescent emissions and selective single-line oscillations have been obtained in the range from 11 to 13 μm. The results make possible the design of a NH3 Stark cell allowing a 1 GHz shift of the 10.78 μm NH3 emission line.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00693893
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 40
    Digitale Medien
    Digitale Medien
    On the relation between genetic and environmental variability in animals (1982)
    Springer
    Journal of molecular evolution 18 (1982), S. 310-314 
    Details
    ISSN: 1432-1432
    Schlagwort(e): Neutral mutation theory ; Natural selection ; Protein evolution ; Levene model ; Environmental variability ; Genetic variability ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary If a phenotypic character is under stabilizing selection, the selective disadvantage of a nonoptimal genotype will decrease exponentially to zero as the proportion of phenotypic variation that is environmental in origin -V e /V p - increases. Under the modified mutation-drift hypothesis of genetic polymorphism, the proportion of mutations that are effectively neutral and average heterozygosity should increase with this ratio. Invertebrates, because of their small size, fast development, and low degree of homeostasis (relative to vertebrates), are expected to show a larger environmental component of phenotypic variation than vertebrates. This may help explain why invertebrates are in general more genetically variable than vertebrates and why, when laboratory populations ofDrosophila are maintained in heterogeneous environments, genetic variability is lost less rapidly than when they are kept in constant conditions.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01733897
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 41
    Digitale Medien
    Digitale Medien
    Adjacent chromosomal regions can evolve at very different rates: Evolution of theDrosophila 68C glue gene cluster (1984)
    Springer
    Journal of molecular evolution 20 (1984), S. 251-264 
    Details
    ISSN: 1432-1432
    Schlagwort(e): Drosophila ; Genome evolution ; 68C Glue gene cluster ; Drosophila melanogaster species subgroup
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The 68C puff is a highly transcribed region of theDrosophila melanogaster salivary gland polytene chromosomes. Three different classes of messenger RNA originate in a 5000-bp region in the puff; each class is translated to one of the salivary gland glue proteins sgs-3, sgs-7, or sgs-8. These messenger RNA classes are coordinately controlled, with each RNA appearing in the third larval instar and disappearing at the time of puparium formation. Their disappearance is initiated by the action of the steroid hormone ecdysterone. In the work reported here, we studied evolution of this hormone-regulated gene cluster in themelanogaster species subgroup ofDrosophila. Genome blot hybridization experiments showed that five other species of this subgroup have DNA sequences that hybridize toD. melanogaster 68C sequences, and that these sequences are divided into a highly conserved region, which does not contain the glue genes, and an extraordinarily diverged region, which does. Molecular cloning of this DNA fromD. simulans, D. erecta, D. yakuba, andD. teissieri confirmed the division of the region into a slowly and a rapidly evolving protion, and also showed that the rapidly evolving region of each species codes for third instar larval salivary gland RNAs homologous to theD. melanogaster glue mRNAs. The highly conserved region is at least 13,000 bp long, and is not known to code for any RNAs.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF02104731
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 42
    Digitale Medien
    Digitale Medien
    Observation and assignment of submillimetre laser lines from CH3OH pumped by isotopic CO2 lasers (1982)
    Springer
    Applied physics 27 (1982), S. 19-25 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract New laser lines have been generated using methanol when isotopically labelled CO2 is used in the pump laser. 19 lines have been found when13C16O2 is used and 29 when12C18O2 is used. The wavelengths of the emission lines have been measured with a relative accuracy of 5×10−3 using the submillimetre resonator as a scanning Fabry-Perot interferometer, and the polarizations of the lines have also been measured. Some of the laser lines have been assigned to pure rotational transitions in the excited state associated with the CO stretching mode, other lines are believed to originate from pumping in combination bands.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697292
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 43
    Digitale Medien
    Digitale Medien
    A new method of measuring ultra-short coherent light pulses (1982)
    Springer
    Applied physics 27 (1982), S. 177-181 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract A new method of pulse width measurement based on the total energy response of an etalon is presented. The theory is developed and results for several pulse shapes are given. The method is unique because no fast response detector is required and there are practically no spectral region limitations.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697437
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 44
    Digitale Medien
    Digitale Medien
    Applications of ps-pulses (1982)
    Springer
    Applied physics 28 (1982), S. 246-254 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.80 ; 42.65 ; 34 ; 42.55 ; 42.70 ; 78
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697852
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 45
    Digitale Medien
    Digitale Medien
    Theory II (1982)
    Springer
    Applied physics 28 (1982), S. 255-261 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55 ; 36.20 ; 36.10 ; 02 ; 36 ; 42.80
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697853
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 46
    Digitale Medien
    Digitale Medien
    On a free-electron-laser in a uniform magnetic field. A solution for arbitrarily strong electromagnetic radiation fields (1982)
    Springer
    Applied physics 27 (1982), S. 15-18 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 41 ; 42.55 ; 95
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Exact expressions are derived for the gain of a free-electron laser based on a uniform longitudinal magnetic field configuration operating in the single-particle, low-gain regime. The gain is calculated for different parameters of the system. For strong enough a field, the gain decreases with an increase of the amplitude, becoming negative when passing a threshold value, which depends on the system parameters. Implications regarding the saturation of the lasing process are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697291
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 47
    Digitale Medien
    Digitale Medien
    Pure MW Raman laser emission in superradiant mode in ammonia by pumping with 9P20 CO2 laser line (1984)
    Springer
    Applied physics 34 (1984), S. 33-35 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 33.80 Bx ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract In this work, clear FIR Raman emission in ammonia was observed when a 9P20 CO2 line was used as a pump. We have noted an intense pump depletion and strong superradiant FIR and MIR emissions. The time history of these radiations has also been recorded. The intense MIR radiation is a new line observed in the ammonia laser.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697462
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 48
    Digitale Medien
    Digitale Medien
    Optical klystron experiments for the ACO storage ring Free Electron Laser (1984)
    Springer
    Applied physics 34 (1984), S. 207-219 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.60 ; 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract To improve the gain in the Orsay storage ring Free Electron Laser (FEL) experiment, the 17 period permanent magnet undulator has been modified to form an optical klystron (OK). We report the measurement of spontaneous emission and the effects on it of energy spread and angular spread. Gain and laser induced bunch lengthening measurements with the OK are also reported and are in very good agreement with the FEL classical theory. The spontaneous emission spectrum which is easy to measure with good signal to noise ratio, turns out to be a very good diagnostic tool forenergy spread and angular spread measurements on storage rings. The factor of four increase in the small gain obtained by converting the undulator NOEL into an OK was the critical factor in the recent operation of the ACO storage ring laser above threshold.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697637
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 49
    Digitale Medien
    Digitale Medien
    Xe2Cl fluorescence and absorption in self-sustained discharge XeCl lasers (1984)
    Springer
    Applied physics 35 (1984), S. 167-172 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.55
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract Fluorescence at 490 nm from the triatomic excimer Xe2Cl* has been investigated to determine the 308 nm absorption due to this species in an x-ray preionized, self-sustained gas discharge XeCl laser. The dependence of Xe2Cl* density on laser intensity (at 308 nm), buffer gas and Xe and HCl partial pressures has been determined for discharges with a peak electrical power deposition of 2.5 GWl−1. Xe2Cl* absorption is estimated to reach 0.6% cm−1 under non-lasing conditions but decreases to a non-saturable 0.2% cm−1 for intracavity laser intensity〉1 MW cm−2. XeCl* and Xe2Cl* fluorescence intensities were found to be a similar for both helium and neon buffer gases but laser output was a factor of two greater with a neon buffer.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697708
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 50
    Digitale Medien
    Digitale Medien
    New lasers II (1982)
    Springer
    Applied physics 28 (1982), S. 233-239 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 42.70 ; 42.55 ; 42.80
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697850
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 51
    Digitale Medien
    Digitale Medien
    Laser fusion (1982)
    Springer
    Applied physics 28 (1982), S. 269-273 
    Details
    ISSN: 1432-0649
    Schlagwort(e): 52 ; 42.55 ; 42.80 ; 51
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00697855
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 52
    Digitale Medien
    Digitale Medien
    Mutations affecting the pattern of the larval cuticle inDrosophila melanogaster (1984)
    Springer
    Development genes and evolution 193 (1984), S. 267-282 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Larval cuticle ; Pattern formation ; Embryonic lethal mutations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary In a search for embryonic lethal mutants on the second chromosome ofDrosophila melanogaster, 5764 balanced lines isogenic for an ethyl methane sulfonate (EMS)-treatedcn bw sp chromosome were established. Of these lines, 4217 carried one or more newly induced lethal mutations corresponding to a total of 7600 lethal hits. Eggs were collected from lethal-bearing lines and unhatched embryos from the lines in which 25% or more of the embryos did not hatch (2843 lines) were dechorionated, fixed, cleared and scored under the compound microscope for abnormalities of the larval cuticle. A total of 272 mutants were isolated with phenotypes unequivocally distinguishable from wild-type embryos on the basis of the cuticular pattern. In complementation tests performed between mutants with similar phenotype, 48 loci were identified by more than one allele, the average being 5.4 alleles per locus. Complementation of all other mutants was shown by 13 mutants. Members of the complementation groups were mapped by recombination analysis. No clustering of loci with similar phenotypes was apparent. From the distribution of the allele frequencies and the rate of discovery of new loci, it was estimated that the 61 loci represent the majority of embryonic lethal loci on the second chromosome yielding phenotypes recognizable in the larval cuticle.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848156
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 53
    Digitale Medien
    Digitale Medien
    Isolation and characterization of temperature-sensitivelethal (2) giant larva alleles (1984)
    Springer
    Development genes and evolution 193 (1984), S. 90-97 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Temperature-sensitive ; Neoplasms ; Differentiation ; Imaginal discs
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary EMS induced temperature-sensitivelethal (2) giant larva, 1(2)gl, alleles were isolated by screening against a knownl(2)gl allele. Analysis of the lethal phase of thel(2)gl ts-deficiency heterozygotes demonstrated: (1) the majority of thel(2)gl tslarvae survive to late third instar, (2) at 29°C the majority of thel(2)gl tslarvae failed to pupate and only rarely did they differentiate adult cuticular structures, (3) at 15°C the majority of the larvae pupated and frequently differentiated adult cuticular structures. Examination of the imaginal discs ofl(2)gl tslarvae reared at 29°C revealed the presence of morphologically abnormal wing, haltere and leg imaginal discs. No morphologically abnormal discs were found in thel(2)gl tslarvae reared at 15°C. Studies on both the histology and the developmental capacity of the morphologically normal and abnormall(2)gl tsdiscs were performed. The morphologically normal discs are histologically normal and produce a full complement of adult cuticular structures. However, the morphologically abnormal discs contained both regions that maintained the normal monolayer epithelium and regions that had lost the normal tissue architecture. The implants obtained when the morphologically abnormal discs are injected into metamorphosing larvae contained only a limited number of the normal complement of adult structures and usually only structures found in the ventral wing hinge region were recovered. In addition, the “metamorphosed” morphologically abnormal discs contained undifferentiated tissue that gave rise to transplantable neoplasms when cultured in adults. The results of the studies on the pathology of thel(2)gl tslarvae are discussed with respect to the role of thel(2)gl tsfunction during normal development, the autonomy of the neoplastic development of thel(2)gl tstissues, and similarities between neoplastic development inDrosophila and mammals.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848636
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 54
    Digitale Medien
    Digitale Medien
    Heterospecific combinations of germ cells and gonadal soma betweenDrosophila melanogaster, D. mauritiana andD. ananassae (1984)
    Springer
    Development genes and evolution 194 (1984), S. 99-106 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Pole cell transplantation ; Heterospecific combinations ; Gametogenesis ; Chorion morphology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary We transplanted pole cells betweenDrosophila melanogaster, D. mauritiana andD. ananassae to investigate the ability of germ cells to develop in the gonad of a heterospecific host, and to study the interaction between somatic follicle cells and the cells of the germ line in producing the species-specific chorion. FemaleD. mauritiana germ cells in aD. melanogaster ovary produced functional eggs with normal development potential. The same is true for the reciprocal combination. FemaleD. ananassae pole cells in aD. melanogaster host only developed to a very early stage and degenerated afterwards. None of the interspecific combinations of male pole cells led to functional sperm. We could not determine at what stage the transplanted male pole cells were arrested. The cooperation of follicle cells and the oocyte-nurse cell complex in producing the chorion was studied using the germ-line-dependent mutationfs(1) K10 ofD. melanogaster, which causes fused respiratory appendages and an abnormal chorion morphology. Wild-type femaleD. mauritiana germ cells in a mutantfs(1) K10 D. melanogaster ovary led to the production of wild-type eggs withD. melanogaster-specific, short respiratory appendages. On the other hand,D. melanogaster fs(1) K10 germ cells in aD. mauritiana ovary induced the formation of eggs with mutant fused appendages which were, however, typicallyD. mauritiana in length. When.D. mauritiana pole cells developed in aD. melanogaster ovary, the chorion exhibited a new imprint pattern that differs from both species-specific patterns.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848349
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 55
    Digitale Medien
    Digitale Medien
    Correlation between adult transformation and aldehyde oxidase staining pattern in wing discs ofApterous genotypes inDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 285-288 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal discs ; homoeosis ; Compartments ; Aldehyde oxidase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The aldehyde oxidase staining pattern in wing discs ofDrosophila melanogaster bearing the genotypesap blt /ap blt andap blt andap blt /ap 73n showns changes from the wild-type pattern. Extensive areas of the presumptive dorsal posterior wing blade, which are normally unstained, have enzyme activity in these mutants. In wings of these genotypes, dorsal posterior structures are replaced by dorsal anterior wing structures. A strong correlation has been found between the frequencies of various staining patterns in the discs and the extent of transformation in the cuticular structures of the wing, which is consistent with the idea that aldehyde oxidase activity can be used as an indicator in the wing disc of this transformation. Unlike the homoeotic mutationengrailed, apterous has not been interpreted as a selector gene yet the work reported here shows thatapterous alleles can cause changes resembling those of theengrailed phenotype both in aldehyde oxidase staining behaviour and in the cuticular transformation.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848418
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 56
    Digitale Medien
    Digitale Medien
    Effects of the “sexcombless” chromosome (In(1)sx) on males and females ofDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 264-269 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Sexcombless ; Foreleg basitarsus ; Genital disc
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The chromosome which carries the mutationsexcombless (In(1)sx) affects males and females ofD. melanogaster. In the male foreleg basitarsi the number of sexcomb teeth is dramatically reduced from 10 to 0.7 and the number of transverse rows of bristles is increased from 6 to 8. Females homozygous forIn(1)sx show a normal bristle pattern in the foreleg basitarsus. The genital disc derivatives of both male and femaleIn(1)sx flies are strongly affected. While the external genitalia show a duplicated or a reduced bristle pattern, the internal genitalia are mostly absent. However, the sexually dimorphic tergites and sternites of the abdomen remain unaffected. The male-specific effect on the basitarsus and the general effects on the genital disc derivatives are proposed to represent two different phenotypic effects ofIn(1)sx which may derive from mutations at different gene loci in the inverted chromosome.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848414
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 57
    Digitale Medien
    Digitale Medien
    Growth is required for cell competition in the imaginal discs ofDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 289-291 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal discs ; Cell competition
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Imaginal wing discs from late third-instar larvae were gammairradiated to induce clones of rapidly growingMinute − cells in a background of slowly growingMinute cells and culturedin vivo for periods up to 18 days. Clones in discs cultured for 16 to 18 days did not grow significantly larger than clones in uncultured controls, indicating that competition between populations of cells having potentially different mitotic rates does not occur in imaginal discs after their growth is completed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848419
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 58
    Digitale Medien
    Digitale Medien
    Isolation and characterization of temperature-sensitivelethal(2)giant larva alleles (1984)
    Springer
    Development genes and evolution 193 (1984), S. 98-107 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Neoplasms ; Promotion ; Regeneration ; Temperature-sensitive ; Imaginal discs
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary In this paper we present an analysis of the behavior ofl(2)gl tsimaginal wing discs during culture in adult hosts. Thel(2)gl tslarvae reared at 29° C contain two types of wing discs, those that are morphologically normal and those that are abnormal. When discs of both types are cultured in adult hosts at 29° C, the restrictive temperature, they give rise to transplantable neoplastic tissue. However, when the 29° C reared discs are cultured at 15° C, the permissive temperature, the morphologically normal discs maintain their morphology, but the morphologically abnormal discs give rise to neoplasms. Thel(2)gl tslarvae reared at 15° C contain only morphologically normal discs. When these discs are cultured in adult hosts at 29° C they give rise to neoplasms, however if the discs are cultured at 15° C they maintain their normal morphology. These results demonstrate: (1) that all wing imaginal discs obtained from 29° C rearedl(2)gl tslarvae are competent to undergo neoplastic development, (2) the morphologically abnormal discs obtained from the 29° C rearedl(2)gl tslarvae are committed to neoplastic development, (3) the neoplastic development of the morphologically normal discs is temperature dependent, (4) once the neoplastic development of thel(2)gl tsdiscs has been initiated the process is not readily reversible. In addition, the ability ofl(2)gl tswing discs to perform epimorphic regulation was tested by amputating morphologically normal permissively rearedl(2)gl tswing discs and culturing both fragiments at the permissive temperature. Fragments of control wild-type discs maintained their morphology during culture at the permissive temperature. However, both fragments of txel(2)gl tsdiscs became neoplastic. This result is discussed with respect to a possible role for thel(2)gl +function in epimorphic regulation and with respect to the phenomena of tumor promotion in vertebrates.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848637
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 59
    Digitale Medien
    Digitale Medien
    Sequential gene activation by ecdysteroids in polytene chromosomes ofDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 103-111 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Polytene Chromosomes ; Ecdysteroids ; Fat Body
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Changes in polytene chromosome 3 L puffing patterns in the fat body ofDrosophila melanogaster larvae and prepupae are compared to those in the salivary gland. While some general features are common to the two tissues, there are differences which reflect their different developmental roles. In vitro experiments with fat body chromosomes show that they have a distinct response to ecdysteroids which is different from that of salivary gland chromosomes, and which does not,in this culture system, reproduce the changes observed in normal development. In short term culture experiments, the fat body chromosomes appear more sensitive to ecdysteroids than the salivary gland chromosomes and, although 20-OH ecdysone is more active than ecdysone in these assays, the possibility is not excluded that ecdysone has a role in normal development as it appears to alter gene activity at physiological levels in these cells.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848447
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 60
    Digitale Medien
    Digitale Medien
    Homologies of positional information in thoracic imaginal discs ofDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 293-300 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal discs ; Positional information ; Homology ; Intercalary regeneration
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The regulative behavior of fragments of the imaginal discs of the wing and first leg was studied when these fragments were combined with fragments of other thoracic imaginal discs. A fragment of the wing disc which does not normally regenerate when cultured could be stimulated to regenerate by combination with certain fragments of the haltere disc. When combined with a haltere disc fragment thought to be homologous by the criteria of morphology and the pattern of homoeotic transformation, such stimulated intercalary regeneration was not observed. Combinations of first and second leg disc fragments showed that a lateral first leg fragment could be stimulated to regenerate medial structures when combined with a medial second leg disc fragment but not when combined with a lateral second leg disc fragment. Combinations of wing and second leg disc fragments showed that one fragment of the second leg disc is capable of stimulating regeneration from a wing disc fragment while another second leg disc fragment fails to stimulate such regeneration. It is suggested that absence of intercalary regeneration in combinations of fragments of different thoracic imaginal discs is a result of homology or identity of the positional information residing in the cells of the fragments. The pattern of correspondence of positional information revealed by this analysis is consistant with the pattern of homology determined by morphological observation and by analysis of the positional specificity of homoeotic transformation among serially homologous appendages. The implications of the existence of homologous positional information in wing and second leg discs which share a common cell lineage early in development are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848488
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 61
    Digitale Medien
    Digitale Medien
    Gap junctions are non-randomly distributed inDrosophila wing discs (1982)
    Springer
    Development genes and evolution 191 (1982), S. 335-339 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Gap junction ; Wing disc
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The distribution of gap junctions in mature larvalDrosophila melanogaster wing discs was analyzed by means of quantitative electron microscopy. Gap junctions are non-randomly distributed in the proximal-distal disc axis and in the apical-basal cell axis of the epithelium. In the epithelial cells, the surface density, number and length of gap junctions are greatest in the apical cell region and distal disc region. The average gap junction surface density is 0.0572 μm−1 and 2.77% of the lateral cell surface is composed of gap junctions. In the adepithelial cells, the gap junction surface density is 0.0005 μm−1 and 0.06% of the cell surface is composed of gap junctions. No gap junctions were observed between epithelial cells and adepithelial cells. The absolute area of gap junctions was estimated in a proximal-distal strip of cells in the disc and is considerably less in the folded regions of the epithelium compared to the flat notum and wing pouch regions. The results are discussed with respect to pattern formation and growth control in imaginal discs.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848494
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 62
    Digitale Medien
    Digitale Medien
    Dicephalic — ADrosophila mutant affecting polarity in follicle organization and embryonic patterning (1982)
    Springer
    Development genes and evolution 191 (1982), S. 28-36 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Polarity ; Maternal effect ; Nurse cells ; Embryogenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The mutationdicephalic (dic) affects follicle development and thereby alters the antero-posterior polarity of embryonic patterning. It maps at a single locus (3–46.0±1.0) and can be characterized as a semi-dominant maternal effect mutation with low penetrance. Indic follicles, the 15 nurse cells form two clusters located at opposite poles of the oocyte; the numerical distribution of the nurse cells among the clusters varies from 7:8 to 1:14. Thedic egg shell carries a micropyle (anterior marker) at either pole, but the misshapen respiratory appendages are restricted to one of the two poles in most eggs. The malformed eggs rarely yield larvae and these are always abnormal anteriorly and/or posteriorly. The segment pattern expressed in their cuticle may represent two anterior parts of opposite polarities (double head type), two posterior parts of opposite polarities (double abdomen type, rare) or show uniform polarity. Lability of organization at the cystocyte stage appears as the primary developmental defect of the mutant.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848543
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 63
    Digitale Medien
    Digitale Medien
    Changes in the distribution of gap junctions inDrosophila melanogaster wing discs during the third larval and early pupal stages of development (1984)
    Springer
    Development genes and evolution 193 (1984), S. 187-196 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Gap junction ; Imaginal disc ; Pattern formation ; EM Stereology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary Developmental changes in the distribution of gap junctions in early, mid and late third larval stage wing discs and in pupariation+6 h and pupariation+24 h stage wing discs fromDrosophila melanogaster were analyzed by quantitative electron microscopy. Gap junctions occur in all 12 intradisc regions examined in each of the five developmental stages. Their distribution is non-random and changes during development which suggests that they are developmentally regulated. The gap junctions are not static structures, rather they grow and regress during development. The changes tend to be gradual ones without sudden increases or decreases. Gap junctions continuously form and grow in size throughout the third larval stage and during the first 6 h following pupariation. Their surface density, number, percent of the lateral plasma membrane area, and absolute area as well as the lateral plasma membrane surface density all increase during this time. Between pupariation+ 6 h and pupariation+24 h all but one of these parameters decrease indicative of gap junctional breakdown. Gap junctions are most numerous and change least during development in the apical cell regions where intercellular contacts are close and stable. They change most in the basal cell regions where intercellular contacts tend to be looser and change during development. The most dramatic change is in the absolute area which increases by a factor of 23 between the early third larval stage and pupariation+24 h. At pupariation the rate of gap junction growth undergoes a transient increase before the phase of disassembly begins. Developmental changes in gap junction surface density are closely coupled with changes in the lateral plasma membrane surface density which suggests that these may be coregulated. Evidence from mutants suggests that when the number and density of gap junctions fail to increase in proportion to lateral plasma membrane growth, wing disc development will be abnormal. Our results support the idea that some minimum gap junction density is required for normal development and that this must increase as development proceeds. The results are consistent with the notion that gap junctions are involved in pattern formation and growth control and are discussed with respect to the acquisition of competence for metamorphosis, disc growth, disc morphogenesis and changes in the hormonal environment.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01260338
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 64
    Digitale Medien
    Digitale Medien
    Immunocytochemical and electrophoretic studies on the localization of the major haemolymph proteins (ceratitins) inCeratitis capitata during development (1984)
    Springer
    Development genes and evolution 194 (1984), S. 37-43 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Major haemolymph proteins ; Development ; Cuticle ; Immunocytochemistry ; Ceratitis capitata
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The developmental profile of the major haemolymph proteins (ceratitins) inCeratitis capitata was studied. Ceratitin concentration in the haemolymph decreases dramatically during the last days of pupal life, while the amounts of ceratitins in whole organism extracts remain unchanged. By electrophoretic, immunological and immunofluorescence techniques it was revealed that ceratitins are reabsorbed by the fat body and a fraction of them is deposited in the cuticle. The possible role of ceratitins is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848952
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 65
    Digitale Medien
    Digitale Medien
    A clonal analysis of cell lineage and growth in the male and female genital disc ofDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 42-55 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Clonal analysis ; Growth ; Cell lineage ; Genital disc ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary InDrosophila, the terminalia (i.e. internal and external analia and genitalia, except the gonads) are formed by the genital disc. Comparative studies suggested that this disc may have evolved through fusion of the imaginal primordia of the last 3 or 4 abdominal segments. The present report describes the clonal relationships within the complex genital disc. Genetically marked cell clones were induced in male and female embryos and larvae heterozygous for cell marker mutations. 1) Frequencies and sizes of clones suggest that the embryonic disc anlage consists of 14–17 precursor cells: 4–6 for the analia, some 7 for the male genitalia, and 3–4 for the female genitalia. These cells grow exponentially during larval development. 2) In both sexes, the clones were confined to either analia or genitalia, suggesting two separate cell lineages already established at blastoderm. 3) Internal and external genitalia remain in the same compartment at least up to 60 h (end of first instar). 4) A clonal restriction appeared around 84 h (mid second instar), separating a dorsal from a ventral part in the male genitalia. The ventral compartment comprises the ventral part of the lateral plate and clasper, hypandrium, and all internal genitalia. No such boundary was detected in the female. 5) In the female, analia and parovaria originate from the same precursors; another cell lineage forms eighth tergites, vaginal plates, oviduct, receptacle, and spermathecae. 6) In female analia, dorsal and ventral plate share common precursors at least up to 84 h. A medio-lateral boundary may appear at 84 h in the ventral anal plate. No clonal restriction was found in the male analia. 7) At all times, clones could cross between left and right sides of the symmetrical terminalia; they consistently did so via ventral structures. 8) The results are discussed in a phylogenetic context, and we propose that the clonal relations reflect the evolution of the complex genital disc.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848545
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 66
    Digitale Medien
    Digitale Medien
    Maternal effects of zygotic mutants affecting early neurogenesis inDrosophila (1982)
    Springer
    Development genes and evolution 191 (1982), S. 191-201 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Neurogenic mutants ; Maternal effects ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The size of the neurogenic region ofDrosophila melanogaster is under the control of several genes of zygotic expression. Lack of function from any of those genes produces an increase of the size of the neurogenic region at the expense of the epidermal anlage. However, differences exist in the extent of neuralisation achieved by each of the genetic loci upon mutation. The present results show that in the case ofN andmam phenotype differences are due to different contributions of maternal gene expression. This could be shown by studying the phenotype which appeared in mutant embryos when the oocytes developed from homozygous mutant precursor cells. Clones of mutant cells were induced in the germ line of females heterozygous for the neurogenic mutationin trans over germ line dependent, dominant female sterile mutations. After removing maternal information the phenotype ofN andmam mutants became identical in both cases. Furthermore maternal information fromN + was found to be necessary for viability of the wildtype.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848335
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 67
    Digitale Medien
    Digitale Medien
    Clonal analysis ofsex-lethal, a gene needed for female sexual development inDrosophila melanogaster (1982)
    Springer
    Development genes and evolution 191 (1982), S. 211-214 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Clonal analysis ; Sex determination
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The mutationSxl f , located on the X-chromosome, is a sex-limited recessive lethal that specifically kills 2X; 2A flies while it does not affect X; 2A flies (Cline 1978). We have analyzed the role ofSxl f on sex determination by a clonal analysis of a new spontaneous allele,Sxl fLS . Female embryos and larvae heterozygous forSxl fLS were irradiated at different times of development to generate homozygousSxl fLS clones which were recognized by linked marker mutations. We have studied the phenotype of such clones on sexually dimorphic regions of the fly (foreleg basitarsus, 5th, 6th and 7th tergites, analia and external genitalia). Despite their female (2X; 2A) chromosomal constitution, clones homozygous forSxl fLS differentiated male structures. These results confirm and extend the preliminary report of Cline (1979). They show that the wildtype product ofSxl f is required for female development.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848339
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 68
    Digitale Medien
    Digitale Medien
    Mutations affecting the pattern of the larval cuticle inDrosophila melanogaster (1984)
    Springer
    Development genes and evolution 193 (1984), S. 296-307 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Larval cuticle ; Pattern formation ; Embryonic lethal mutations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary In order to identify X-chromosomal genes required inDrosophila for early patterning and morphogenesis, we examined embryos hemizygous for EMS-induced lethal mutations to determine which of those mutations cause gross morphological defects. Embryos from 2711 lethal lines, corresponding to 3255 lethal point mutations were studied. Only 21% caused death during embryogenesis and of these, only one-sixth, or 3% of the total lethals, were associated with defects visible in the final cuticle pattern. Of the 114 point mutants causing visible cuticle defects, 76 could be assigned to 14 complementation groups. An additional 25 mutations mapping to regions of the X-chromosome not covered by male fertile duplications were assigned to six complementation groups based on similarities of map position and phenotype. Thirteen mutations could not be assigned to complementation groups. All mutations allowed normal development through the cellular blastoderm stage, the first defects associated with the earliest acting loci being observed shortly after the onset of gastrulation. The phenotypes of the various loci range from alterations in segment pattern or early morphogenetic movements to defects in final pigmentation and denticle morphology. Cuticle preparations were also examined for 63 deletions spanning in total 74% of the X-chromosome, as well as for 8 deletions and point mutations derived in saturation mutagenesis screens of the fourth chromosome (Hochman 1976). With the exception of defects in head morphology and defects in cuticle differentiation, none of the hemizygous deletions showed phenotypes other than those predicted by point mutations known to lie in those regions. No deletion caused new or unknown alterations in gastrulation, segmentation or cuticle pattern.These results suggest that the number of genes required zygotically for normal embryonic patterning is small and that most, if not all such loci, are represented by point mutations in our collection.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848158
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 69
    Digitale Medien
    Digitale Medien
    The role of the peripodial membrane of leg and wing imaginal discs ofDrosophila melanogaster during evagination and differentiation in vitro (1984)
    Springer
    Development genes and evolution 193 (1984), S. 180-186 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal disc ; Morphogenesis ; Tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The thin region of the peripodial membrane is confined to the area overlying the distal anlagen in thoracic discs. During the early stages of evagination the peripodial membrane is greatly stretched, but does not rupture. The appendage then evaginates through the stalk, probably by means of a contraction of the peripodial membrane. The cells of the peripodial membrane of leg and wing discs persist and differentiate sheets of trichomes characteristic of the ventral and lateral thorax. This is discussed in relation to imaginal disc fate maps.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848893
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 70
    Digitale Medien
    Digitale Medien
    TheUbx syndrome ofDrosophila: the prothoracic transformation (ppx) is independent ofbx, bxd andpbx (1984)
    Springer
    Development genes and evolution 193 (1984), S. 263-265 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Biothorax complex ; Prothoracic transformation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary If, early in development, theUbx + gene is removed by mitotic recombination from cells of the meso-and metathoracic leg primordia, theseUbx − cells develop as in the posterior prothoracic leg. We show that this transformation, termedpostprothorax, is a discrete genetic function that is independent of other homeotic transformations such asbx, pbx orbxd, which also result from the inactivation of theUbx gene.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01260349
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 71
    Digitale Medien
    Digitale Medien
    Mutations affecting the pattern of the larval cuticle inDrosophila melanogaster (1984)
    Springer
    Development genes and evolution 193 (1984), S. 283-295 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Larval cuticle ; Pattern formation ; Embryonic lethal mutations
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The present report describes the recovery and genetic characterization of mutant alleles at zygotic loci on the third chromosome ofDrosophila melanogaster which alter the morphology of the larval cuticle. We derived 12600 single lines from ethyl methane sulfonate (EMS)-treatedst e orrucuca chromosomes and assayed them for embryonic lethal mutations by estimating hatch rates of egg collections. About 7100 of these lines yielded at least a quarter of unhatched eggs and were then scored for embryonic phenotypes. Through microscopic examination of unhatched eggs 1772 lines corresponding to 24% of all lethal hits were classified as embryonic lethal. In 198 lines (2.7% of all lethal hits), mutant embryos showed distinct abnormalities of the larval cuticle. These embryonic visible mutants define 45 loci by complementation analysis. For 32 loci, more than one mutant allele was recovered, with an average of 5.8 alleles per locus. Complementation of all other mutants was shown by 13 mutants. The genes were localized on the genetic map by recombination analysis, as well as cytologically by complementation analysis with deficiencies. They appear to be randomly distributed along the chromosome. Allele frequencies and comparisons with deficiency phenotypes indicate that the 45 loci represent most, if not all, zygotic loci on the third chromosome, where lack of function recognizably affects the morphology of the larval cuticle.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848157
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 72
    Digitale Medien
    Digitale Medien
    Early neurogenesis in wild-typeDrosophila melanogaster (1984)
    Springer
    Development genes and evolution 193 (1984), S. 308-325 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Neurogenesis ; Pattern of neuroblasts ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary This paper deals with morphological aspects of early neurogenesis inDrosophila, in particular with the segregation of neuroblasts from the neurogenic region of the ectoderm and the pattern formed by those wells within both the germ band and the procephalic lobe. The neurogenic ectoderm was found to contain neural precursors intermingled with epidermal precursors, extending from the midline up to the primordia of the tracheal tree along the germ band and laterodorsally in the procephalic lobe. Germ band neuroblasts segregate from the neurogenic ectoderm during a period of several hours according to characteristic spatial and temporal patterns. During the first half of the segregation process the pattern of germ band neuroblasts was found to be the same in different animals in both spatial arrangement and number of cells; this permitted the identification of individual neuroblasts from different embryos. Later in development several difficulties were encountered which precluded an exact description of the neuroblast pattern. The constitution of the neurogenic region is discussed in relation to the phenotype of mutants affecting neurogenesis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848159
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 73
    Digitale Medien
    Digitale Medien
    The spatial arrangement of germ line cells in ovarian follicles of the mutantdicephalic inDrosophila melanogaster (1984)
    Springer
    Development genes and evolution 193 (1984), S. 388-393 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Oogenesis ; Ring canals ; Oocyte determination ; Polarity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The pattern of intercellular connections between germ line cells has been studied in follicles of the mutantdicephalic (dic), which possess nurse cell clusters at both poles. Staining of follicles with a fluorescent rhodamine conjugate of phalloidin reveals ring canals and cell membranes and thus allows us to reconstruct the spatial organization of the follicle. Each germ line cell can be identified by the pattern of cell-cell connections which reflect the mitotic history of individual cells in the 16-cell cluster. The results indicate that in both wild-type anddicephalic cystocyte clusters one of the two cells with four ring canals normally becomes the pro-oocyte. However, in some follicles (dicephalic and wild-type) oocytes were found with fewer or more than four ring canals. Indic follicles, one or several nurse cells may become disconnected from the other cells during oocyte growth at stage 9–10. Such disconnected cells cannot later on empty their cytoplasm into the oocyte. This, in turn, might be of consequence for the determination of axial polarity of the embryo.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848229
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 74
    Digitale Medien
    Digitale Medien
    Cell interactions during the fusionin vitro ofDrosophila eye-antennal imaginal discs (1984)
    Springer
    Development genes and evolution 193 (1984), S. 406-413 
    Details
    ISSN: 1432-041X
    Schlagwort(e): Drosophila ; Imaginal disc ; Morphogenesis ; Tissue culture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The fusion of the eye-antennal discs during culturein vitro has been investigated, and the complex morphogenetic movements which occur during the formation of the head capsule of the insect are described. The initial contact between the eye anlagen is by means of cell processes spanning the gap between the two discs. Subsequently the two epithelia become firmly apposed, and then the integrity of the epithelium in the region of fusion breaks down, cells appearing to move to new positions in order to form an epithelium which unites the two discs. The epithelium eventually secretes a pattern of cuticular structures which is continuous between the derivatives of the two discs. Bristles on either side of the line of fusion are perfectly aligned, and structures such as the median ocellus, which are formed jointly by the cells of the two discs, differentiate normally. This is also found when left and right eye-antennal discs of different genotypes are placed side-by-side, indicating that processes of pattern regulation can occur in culture.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00848232
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 75
    Digitale Medien
    Digitale Medien
    Localization of phytohemagglutinin in the embryonic axis of Phaseolus vulgaris with ultra-thin cryosections embedded in plastic after indirect immunolabeling (1984)
    Springer
    Planta 162 (1984), S. 548-555 
    Details
    ISSN: 1432-2048
    Schlagwort(e): Immunocytochemistry ; Lectin (localization) ; Phaseolus (lectin) ; Phytohemagglutinin ; Seed (lectin)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract We have examined the properties and subcellular localization of phytohemagglutinin (PHA), the major lectin of the common bean (Phaseolus vulgaris.), in the axis cells of nearly mature and imbibed mature seeds. On a protein basis the axis contained about 15% as much PHA as the cotyledons. Localization of PHA was done with an indirect immunolabeling method (rabbit antibodies against PHA, followed by colloidal gold particles coated with goat antibodies against rabbit immunoglobulins) on ultra-thin cryosections which were embedded in plastic on the grids after the immunolabeling procedure. The embedding greatly improved the visualization of the subcellular structures. The small (4 nm) collodial gold particles, localized with the electron microscope, were found exclusively over small vacuoles or protein bodies in all the cell types examined (cortical parenchyma cells, vascular-bundle cells, epidermal cells). The matrix of these vacuoles-protein bodies appears considerably less dense than that of the protein bodies in the cotyledons, but the results confirm that in all parts of the embryo PHA is localized in similar structures.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00399921
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 76
    Digitale Medien
    Digitale Medien
    Tissue-specific and substrate-specific detection of aldehyde and pyridoxal oxidase in larval and imaginal tissues of Drosophila melanogaster (1982)
    Springer
    Biochemical genetics 20 (1982), S. 315-332 
    Details
    ISSN: 1573-4927
    Schlagwort(e): aldehyde oxidase ; pyridoxal oxidase ; tissue specificity ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The substrate specificities of aldehyde and pyridoxal oxidases in Drosophila melanogaster have been determined with a variety of aliphatic and aromatic aldehydes. This analysis has led to the discovery that 2,4,5-trimethoxy-benzaldehyde is a specific substrate for pyridoxal oxidase, as based on the histochemical distribution of oxidase activity, the absence of enzymatic activity in the lpo 1strains, and the dosage dependence on the number of lpo +genes present. The tissue-specific localization of aldehyde oxidase (AO) and pyridoxal oxidase (PO) in the larval and adult structures showed that AO was present in all the major internal organs of the larvae and adults, including brain, imaginal discs, Malpighian tubules, digestive system, and reproductive structures. Pyridoxal oxidase is present in many of the same structures which possess AO, but is missing from the cardia, crop, imaginal discs, ovarian follicle cells, paragonia, pericardial cells, and wreath cells. The only structure which possesses PO but lacks AO is the larval salivary gland. These histochemical differences in AO and PO distribution were also confirmed by enzymatic analysis of the activities present in homogenates of ovaries, paragonia, and salivary glands. The general pattern of enzyme expression appears to be established during embryogenesis and maintained throughout the life of the individual.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484427
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 77
    Digitale Medien
    Digitale Medien
    Selection at the α-Gpdh locus in experimental populations of Drosophila melanogaster (1982)
    Springer
    Biochemical genetics 20 (1982), S. 461-474 
    Details
    ISSN: 1573-4927
    Schlagwort(e): Drosophila ; allozymes ; α-Gpdh ; selection ; genetic background
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Three sets of experiments have been conducted in order to evaluate the role of natural selection at the α-Gpdh locus in Drosophila melanogaster. (1) The evolution of the F-allele frequency has been followed for many generations in 13 experimental populations having different genetic backgrounds. (2) Egg-to-adult viability has been measured in synthetic populations derived from one locality (Brouilly) and the results have been compared with those of a previous experiment involving a different local population (Tostes). (3) The effects of sodium octanoate on egg-to-adult viability have been measured on the genotypes FF, FS, SF, and SS. The results demonstrate that selection operates on a small block of genes which includes the α-Gpdh locus.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484697
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 78
    Digitale Medien
    Digitale Medien
    An esterase duplication in Drosophila: Differences in expression of duplicate loci within and among related species (1982)
    Springer
    Biochemical genetics 20 (1982), S. 929-942 
    Details
    ISSN: 1573-4927
    Schlagwort(e): esterase ; duplication ; gene expression ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract An esterase duplication is described in the sibling species pair Drosophila mojavensis and Drosophila arizonensis. We present evidence for two separate structural loci mapping at a distance of less than 0.16 recombination units from each other. Alleles at the two loci have the same substrate specificities and form small amounts of interlocus heterodimers. One locus (Est-5) is functioning throughout the insect's life cycle and appears at high concentrations in the hemolymph and the fat body. Its duplicate (Est-4) functions only during the late larval stage and is concentrated mainly in the carcass. No null alleles at either locus were observed in population surveys. An examination of 12 other species from the repleta group, to which D. mojavensis and D. arizonesis belong, suggests that Est-5 is universally present, but the activity levels of Est-4 vary among species and may be totally absent in some species. Variation in the level of Est-4 activity does not closely follow the phylogenetic relationship.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484070
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 79
    Digitale Medien
    Digitale Medien
    The association between malathion resistance and acetylcholinesterase in Drosophila melanogaster (1982)
    Springer
    Biochemical genetics 20 (1982), S. 179-198 
    Details
    ISSN: 1573-4927
    Schlagwort(e): acetylcholinesterase ; Drosophila ; malathion ; insecticide resistance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The relationship between the 50% survival time for flies feeding on a malathion-containing medium and the activity of acetylcholinesterase (AChE) was determined for 15 isofemale lines of Drosophila melanogaster. A significant correlation was found (r=0.28, P〈0.05), with more resistant lines tending to have a lower level of AChE activity. An association between AChE and malathion resistance was also observed in a selection experiment. The AChE activity decreased in two of two populations selected for malathion resistance. AChE from these populations was altered in kinetic parameters (measured in crude head extracts) and electrophoretic mobility. Although the “resistant” AChE had a lower activity (V m) on either a per milligram protein or a per individual basis, its apparent K m for acetylthiocholine was lower than that of “susceptible” AChE. Recombination mapping of both low activity and fast electrophoretic mobility localized these traits to the region of the structural locus (Ace) on the third chromosome. The AChE activity of flies heterozygous for a variety of Ace lesions (kindly provided by Dr. W. M. Gelbart) was consistent with this location. The changes in AChE were suggested to have been caused by selection of alleles at the Ace locus.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484945
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 80
    Digitale Medien
    Digitale Medien
    Variation in the biochemical properties of the Drosophila alcohol dehydrogenase allozymes (1984)
    Springer
    Biochemical genetics 22 (1984), S. 153-168 
    Details
    ISSN: 1573-4927
    Schlagwort(e): alcohol dehydrogenase ; Drosophila ; activity ratio ; specific activity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Thirteen Drosophila Adh variants have been characterized with respect to gene expression, substrate preference, thermostability, and specific activity. The results suggest that the variants may be grouped into two biochemical classes, typified by the properties of the two most common enzyme forms, ADH-F and ADH-S. Membership of these classes cannot be predicted from electrophoretic mobility, nor is any simple classification possible with regard to the characteristics of level of gene expression (in terms of ADH activity or ADH protein) or thermostability of the gene product.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00499295
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 81
    Digitale Medien
    Digitale Medien
    Acetaldehyde utilization and toxicity in Drosophila adults lacking alcohol dehydrogenase or aldehyde oxidase (1984)
    Springer
    Biochemical genetics 22 (1984), S. 1015-1029 
    Details
    ISSN: 1573-4927
    Schlagwort(e): acetaldehyde ; alcohol dehydrogenase ; aldehyde oxidase ; Drosophila
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Metabolic utilization and toxicity of acetaldehyde were studied in flies lacking alcohol dehydrogenase (ADH), aldehyde oxidase (AO), or both functions. Prior to the experiments, mutant alleles Adh n4 and mal were transferred to the same genetic background by 10 successive backcrosses. By comparison with wild-type flies, various deleterious, pleiotropic effects could be attributed to the mal allele but not to Adh n4 . Of the four genotypes studied (mal, Adh n4 , mal Adh n4 , and wild), all were able to use acetaldehyde as a resource in a similar way. In spite of its high toxicity, acetaldehyde appeared a better resource than ethanol. Flies treated with intermediate acetaldehyde concentrations (around 0.5%) exhibited a very high interindividual heterogeneity which could reflect a physiological adaptation occurring as a consequence of the aldehyde treatment. Toxicity tests showed that ADH-negative flies were more sensitive to acetaldehyde than wild type, but this is most likely explained by the transformation of the aldehyde into alcohol. Our results show that the aldehyde metabolizing enzyme (AME) system in Drosophila is neither ADH nor AO. The existence of an aldehyde dehydrogenase is plausible.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00499628
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 82
    Digitale Medien
    Digitale Medien
    Genetic, ontogenetic, and tissue-specific variation of dipeptidases in Drosophila melanogaster (1982)
    Springer
    Biochemical genetics 20 (1982), S. 407-424 
    Details
    ISSN: 1573-4927
    Schlagwort(e): dipeptidases ; Drosophila ; variation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Three dipeptidases in Drosophila melanogaster are under independent genetic control and their structural genes have been localized, Dip-A to 2R and Dip-B and Dip-C to 3R (Voelker and Langley, 1978; Ohnishi and Voelker, 1981). These enzymes were characterized with respect to their substrate specificities, genetic variability (electrophoretic mobility and quantitative activity level), ontogeny (activity and isozyme pattern), and tissue localization. The dipeptide substrate specificities of DIP-A and DIP-B overlap each other considerably, but do not overlap with DIP-C. In natural populations, DIP-B and DIP-C are essentially monomorphic electrophoretically whereas DIP-A is polymorphic for three allozymes. Both DIP-A and DIP-B show quantitative genetic variation of activity level within an allozyme class. All three enzymes are expressed at all stages in the life cycle, but DIP-A and DIP-B activities vary considerably according to developmental stage and sex of adult. The tissue localizations of DIP-A and DIP-B activities show similar patterns and a nearly ubiquitous occurrence of both enzymes, but with particularly high values in larval and adult midguts and in the adult female reproductive system. These results suggest a general metabolic role for the enzymes, such as regulation of the concentrated pools of amino acids and oligopeptides found in Drosophila tissues.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00484692
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 83
    Digitale Medien
    Digitale Medien
    Role of glandular scales of lepidote rhododendrons in insect resistance (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 1787-1798 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coleoptera ; Curculionidae ; Otiorhynchus sulcatus (F.) ; black vine weevil ; Ericaceae ; Rhododendron ; trichomes ; glandular scales ; essential oils ; volatiles ; plant resistance
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Glandular scales on selected lepidote rhododendron species varied in density from 109 ± 13 to 4180 ± 60/cm2 of leaf surface. Globules contained within the scales stained with Sudan IV, a lipophilic dye. Essential oil contents of the scales varied with species from 24 ± 8 to 151 ± 35 ng/scale. Black vine weevil [(Otiorhynchus sulcatus (F.)] feeding on leaves from a sample of rhododendron species was inversely related to leaf essential oil content, and weevil feeding on membrane filters was inhibited by application of essential oil extracts from leaves of most lepidote rhododendrons tested. Results suggest that the glandular scales of the lepidote rhododendrons function, at least in part, in plant defense against insects.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987361
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 84
    Digitale Medien
    Digitale Medien
    Attraction of bark beetles (Coleoptera: Scolytidae) to a pheromone trap (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 723-752 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Ips typographus ; pheromone ; release ; recapture ; diffusion ; model ; Coleoptera ; Scolytidae ; trap ; marking ; dispersal
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The movement of bark beetles near an attractive pheromone source is described in terms of mathematical models of the diffusion type. To test the models, two release experiments involving 47,000 marked spruce bark beetles [Ips typographus (L.)] were performed. The attractive source was a pheromone trap, surrounded by eight concentric rings with eight passive trap stations on each ring. Captures were recorded every 2–10 minutes for the pheromone trap and once for the passive traps. The models were fitted to the distribution in time of the central pheromone trap catch and to the spatial distribution of catch among the passive traps. The first model that gives a reasonable fit consists of two phases: Phase one—After release the beetles move according to a diffusion process with drift towards the pheromone trap. The strength of the drift is inversely proportional to the distance from the traps. Phase two—those beetles attracted to, but not caught by, the pheromone trap are no longer influenced by the pheromone, and their movement is described by a diffusion process without drift. In phase two we work with a loss of beetles, whereas the experiment seems to indicate that the loss of beetles in phase one is negligible. As a second model, the following modification of phase one is considered: After release the beetles move according to a diffusion process without drift, until they start responding to the pheromone (with constant probability per unit time), whereafter they start moving according to a diffusion process with drift. This study, like other release experiments, shows that the efficiency of the pheromone trap is rather low. What is specific for the present investigation is that we try to explain this low efficiency in terms of dynamic models for insect movement. Two factors seem to contribute: Some beetles do not respond to pheromone at all, and some beetles disappear again after having been close to the pheromone trap. It also seems that the motility of the beetles decreased after they ceased responding to the pheromone. Furthermore, the data lend some support to the hypothesis that flight exercise increases the response of the beetles to pheromone.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00988539
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 85
    Digitale Medien
    Digitale Medien
    Receptor cells inIps typographus andDendroctonus micans specific to pheromones of the reciprocal genus (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 759-769 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Ips typographus ; Dendroctonus micans ; Coleoptera ; Scolytidae ; exo-brevicomin ; (+)-ipsdienol ; single-cell recordings ; interspecific attraction
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Olfactory receptor cells were studied electrophysiologically inIps typographus andDendroctonus micans. The investigation revealed cells which were keyed to pheromone compounds characteristic of the reciprocal genus. Thus, cells keyed toexo-brevicomin were found inI. typographus, whereas cells keyed to (+)-ipsdienol were present inD. micans. Laboratory behavioral tests indicated an attractive effect of the two compounds on beetles of the reciprocal genus. InI. typographus the effect ofexo-brevicomin predominantly concerned males and enhanced their response to the pheromone “ipslure.” It is suggested thatexo-brevicomin serves as an interspecific attractant forI. typographus, which may be guided by pheromone compounds of the reciprocal genus in finding suitable breeding material. The function of (+)-ipsdienol inD. micans is more uncertain. It may be either a pheromone or an interspecific messenger.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00988541
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 86
    Digitale Medien
    Digitale Medien
    Olfaction in the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae): Electroantennogram studies (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 1759-1785 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Cotton boll weevil ; Anthonomus grandis ; Coleoptera ; Curculionidae ; pheromone ; kairomone ; plant odor ; olfaction ; electroantennogram ; attractant ; host plant ; green leaf volatiles
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Electroantennogram (EAG) techniques were utilized to measure the antennal olfactory responsiveness of adult boll weevils,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to 38 odorants, including both insect and host plant (Gossypium hirsutum L.) volatiles. EAGs of both sexes were indicative of at least two receptor populations: one receptor population primarily responsive to pheromone components and related compounds, the other receptor population primarily responsive to plant odors. Similar responses to male aggregation pheromone components (i.e., compounds I, II, and III + IV) were obtained from both sexes, but females were slightly more sensitive to I. Both sexes were highly responsive to components of the “green leaf volatile complex,” especially the six-carbon saturated and monounsaturated primary alcohols. Heptanal was the most active aldehyde tested. More acceptors responded to oxygenated monoterpenes than to monoterpene hydrocarbons. β-Bisabolol, the major volatile of cotton, was the most active sesquiterpene. In general, males, which are responsible for host selection and pheromone production, were more sensitive to plant odors than were females. In fact, males were as sensitive to β-bisabolol and heptanal as to aggregation pheromone components. Electrophysiological data are discussed with regard to the role of insect and host plant volatiles in host selection and aggregation behavior of the boll weevil.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987360
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 87
    Digitale Medien
    Digitale Medien
    Quantitative variation of pheromone components in the spruce bark beetleIps typographus from different attack phases (1984)
    Springer
    Journal of chemical ecology 10 (1984), S. 1029-1055 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Ips typographus ; spruce bark beetle ; Coleoptera ; Scolytidae ; 2-methyl-3-buten-2-ol ; ipsenol ; cis-verbenol ; ipsdienol ; trans-verbenol ; verbenone ; myrtenol ; trans-myrtanol ; 2-phenylethanol ; ß-isophorone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Ips typographus beetles were collected in the field, separated into eight attack phases (from beetles walking on the trunk of a tree under attack to those excavating gallery systems with a mother gallery longer than 4 cm), and immediately frozen in liquid nitrogen. 2-Methyl-3-buten-2-ol,cis- andtrans-verbenol, verbenone, myrtenol, trans-myrtanol, ipsenol, ipsdienol, and 2-phenylethanol were quantified from excised hindguts against an internal standard, heptyl acetate, in the extraction solvent. Methylbutenol, the pinene alcohols, and 2-phenylethanol showed the same pattern of variation between attack phases in males, with the largest amounts present before accepting females and then a fast decline. Ipsenol and ipsdienol were not detected in males before the females were accepted, and the amounts increased when the females start their egg laying. Verbenone occurred only in trace amounts. The beetles were sampled from five Norway spruce trees (Picea abies) of differing resin flow. The correlations between the nine pheromone components and five major host monoterpenes in the gut showed that the variation in the amount of methyl-butenol, ipsenol, and ipsdienol could not be explained by the variation in the amounts of host monoterpenes. In contrast over 80% of the quantitative variation ofcis-verbenol,trans-verbenol, and myrtenol was explained by the amount of α-pinene. The nine pheromone components from 36 individual males were also quantified. Both methylbutenol andcis-verbenol showed a large variation in both amounts and proportions. Females containedtrans-verbenol and traces of most other components found in males. When accepted by the male, they also contained a female-specific compound, β-isophorone. Behavioral and biosynthetic implications of the results are discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987511
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 88
    Digitale Medien
    Digitale Medien
    Electroantennogram responses ofScolytus multistriatus (Coleoptera: Scolytidae) to its pheromone components and to associated compounds (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 1333-1344 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coleoptera ; Scolytidae ; Scolytus multistriatus ; pheromone ; insect olfaction ; electroantennogram ; electrophysiology ; differential adaptation ; multistriatin ; 4-methyl-3-heptanol ; α-cubebene
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Electroantennograms were recorded fromScolytus multistriatus in response to 4-methyl-3-heptanol, the four geometric isomers of multistriatin, and cubeb oil. Charateristic dose-response curves for response amplitude and the time required for the voltage trace to return to 1/2 baseline (recovery rate) were established. Recovery rates were significantly more rapid following stimulation with 4-methyl-3-heptanol or cubeb oil than with the multistriatin isomers. At most intensities, α-multistriatin, the isomer that evokes behavioral response, gave significantly larger EAGs with significantly longer recovery rates than the other isomers. Results of differential adaptation experiments suggested that 4-methyl-3-heptanol interacted with the processes involving multistriatin and cubeb oil activity. However, cross-activity of acceptors for these compounds seems unlikely; single sensillum recordings are needed to ascertain the response spectra for individual receptor neurons.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01403097
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 89
    Digitale Medien
    Digitale Medien
    Frontalin in the male mountain pine beetle (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 1399-1409 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coleoptera ; Scolytidae ; Dendroctonus ponderosae ; pheromone ; frontalin ; exo-brevicomin ; Pinns contorta ; Pinus ponderosa
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Frontalin andexo-brevicomin were identified by GC-MS in air drawn over maleDendroclonus ponderosae Hopk. (MPB) from Oregon that had joined females for 1–2 days in the bark of lodgepole and ponderosa pine logs. Unfed males releasedexo- andendo-brevicomin but not frontalin. These three compounds were not detected in either unfed or fed females. Arrestment of males bytrans-verbenol and terpenes in an olfactory walkway was reduced by the addition of racemic frontalin; production of attractant chirps also diminished. Racemic frontalin also strongly reduced the aggregation of MPB in lodgepole and ponderosa pine stands to sticky traps baited with the aggregation pheromonetrans-verbenol and host terpenes; however, the function of the natural enantiomer of frontalin in MPB is unknown.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01403103
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 90
    Digitale Medien
    Digitale Medien
    Defensive secretions of three oxytelinae rove beetles (Coleoptera: Staphylinidae) (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 1411-1420 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coleoptera ; Staphylinidae ; Oxytelinae ; defensive secretion ; glands ; acetates ; lactones ; alkenes ; quinones ; citral
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The secretions of the abdominal glands ofBledius spectabilis Kraatz,Platystethus arenarius Fourcr., andOxytelus piceus L. have been shown to contain four 1-alkenes; toluquinone; toluhydroquinone; C10 −-,C11 −, C12 −-, and C14 − γ-lactones; C12-δ-lactone; citral; and decyl-, undecyl-, and dodecyl acetates. Quantitative results indicate that 1-alkenes are formed probably from present lactones by decarboxylation. According to the known life histories of the beetles, it is suggested that the gland material is not used as an algal growth regulator but represents a unique defensive blend characteristic for the whole subfamily.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01403104
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 91
    Digitale Medien
    Digitale Medien
    Olfactory responses of adultTribolium castaneum (Herbst), to volatiles of wheat and millet kernels, milled fractions, and extracts (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 1463-1472 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Red flour beetle ; Tribolium castaneum ; Coleoptera ; Tenebrionidae ; food volatiles ; olfactory responses ; olfactometer
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Olfactory responses of 72- to 96-hr-old, 24-hr starved adult male, female, or mixed-sex groups of the red flour beetle,Tribolium castaneum (Herbst), to volatiles from wheat and millet kernels, certain milled fractions, and solvent extracts were recorded by using a lightsensitive apparatus. Wheat-germ volatiles from intact germ or solvent extracts were generally more attractive than volatiles of wheat endosperm or wheat bran. Volatiles of whole wheat kernels were the least attractive among test materials of wheat origin, whereas there were no significant differences among whole wheat flour, germ, and endosperm. Wheat-germ extracts, however, were more attractive than were extracts of the other fractions. Whole millet flour or fermented millet flour volatiles were more attractive than those from whole millet kernels or millet starch. Beetles reached maximum responsiveness to grain volatiles by 72–96 hr after adult ecdysis. Groups of virgin female beetles generally were more responsive than male or mixed-sex groups to volatiles of substances tested.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00989103
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 92
    Digitale Medien
    Digitale Medien
    Influence of opposite sex on attraction produced by pioneer sex of four bark beetle species cohabiting pine in the Southern United States (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 373-378 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Dendroctonus frontalis ; Ips calligraphus ; I. grandicollis ; I. avulsus ; Coleoptera ; Scolytidae ; mating ; attraction
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Catches ofDendroctonus frontalis andIps avulsus on traps surrounding bolts infested with both sexes of each species in the gallery were not significantly different from catches at bolts infested only with the sex which normally pioneers the host colonization process. In contrast, the presence of the second sex in the gallery significantly reduced catches ofI. grandicollis andI. calligraphus and, additionally, the presence of females in the male galleries ofI. calligraphus significantly reduced the catch ofI. avulsus females as compared with their response to bolts infested with the maleI. calligraphus only.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987785
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 93
    Digitale Medien
    Digitale Medien
    Defensive adaptations of eggs and adults ofGastrophysa cyanea (Coleoptera: Chrysomelidae) (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 453-462 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Defensive secretions ; oleic acid ; hydrocarbons ; terpenoids ; eggs ; deterrents ; ants ; predation ; Chrysomelidae ; Coleoptera ; Gastrophysa cyanea ; reflex bleeding ; elytral glands
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Egg clusters and adults ofGastrophysa cyanea are conspicuous and, like their larvae, are chemically protected. The eggs owe their bright yellow color primarily to β-carotene and, in addition, contain substantial quantities of oleic acid. At natural concentrations oleic acid effectively deters many species of ants from feeding. The use of fatty acids as deterrents against ants is discussed as a possible widespread phenomenon among insects. During defensive confrontations, adults ofG. cyanea exhibit avoidance behavior and may also feign death. In addition, the adults may autohemmorhage or secrete a fluid from elytral or pronotal pores in response to traumatic stimuli. The secretions are effective against ants and contain a mixture of hydrocarbons as well as terpenoid components. The pattern of ontogenetic modification in the defensive chemical repertoire ofG. cyanea is discussed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987793
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 94
    Digitale Medien
    Digitale Medien
    Responses of the olfactory receptors ofScolytus scolytus (F.) (Coleoptera: Scolytidae) to the stereoisomers of 4-methyl-3-heptanol (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 477-492 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Scolytus scolytus ; Coleoptera ; Scolytidae ; pheromone ; 4-methyl-3-heptanol stereoisomer ; olfaction ; electrophysiology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Electroantennogram (EAG) and single-cell recording techniques have been used to demonstrate the presence of separate receptors for (−)-threo- and (−)-erythro-4-methyl-3-heptanol on the antenna ofS. scolytus. The majority of single-cell recordings showed spikes of two different amplitudes. The cell giving spikes of larger amplitude responded to the (−)-threo stereoisomer while the cell with the small-amplitude spikes responded to (−)-erythro-4-methyl-3-heptanol. It is suggested that in most recordings the two cells are associated with a single sensillum basiconicum.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00987796
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 95
    Digitale Medien
    Digitale Medien
    Seasonal variation in laboratory response to behavioral chemicals of the southern pine beetle (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 641-652 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Dendroctonus frontalis ; Coleoptera ; Scolytidae ; seasonal variation ; pheromone content ; environmental parameters
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract The response ofDendroctonus frontalis to an attractant mixture (frontalin,trans-verbenol, and loblolly pine turpentine) was measured in the laboratory over a four-year period. Beetle response was highest in late winter and early spring, and lowest in midsummer and early fall. Males consistently responded higher than females. Female beetles displayed significantly higher responses in early morning and late afternoon than in the middle of the day. Analysis of beetle pronotal width and fat content revealed a high degree of correlation between these two parameters in female beetles, but there was no correlation of response with either fat content or pronotal width for either sex. There was no evident relationship between mean monthly beetle response and total amounts of frontalin andtrans-veibenol found in hindgut extracts. Daily temperature in months both during which beetles were bioassayed and immediately prior to bioassay was highly correlated to response to the attractant.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00989633
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 96
    Digitale Medien
    Digitale Medien
    Oscillatoria Sp. (Cyanophyta) mat metabolites implicated in habitat selection inBembidion obtusidens (Coleoptera: Carabidae) (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 671-678 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Bembidion obtusidens ; Coleoptera ; Carabidae ; Oscillatoria animalis ; Oscillatoria subbrevis ; Cyanophyta ; metabolites ; volatiles ; ecophenes ; methylhexadecanoate ; methyloctadecenoate ; attractant ; habitat selection
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract In laboratory bioassaysBembidion obtusidens Fall adults were attracted to volatile metabolites (methyl esters of hexadecanoic and 9-octadecenoic acid) of mat-forming, filamentous blue-green algae (Oscilalatoria sp.; Cyanophyta) growing in the microhabitat of these beetles on the shores of saline lakes. Commercial preparations of these metabolites also were attractive, suggesting thatOscillatoria metabolites are token stimuli which serve as habitat cues forBembidion adults.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00989636
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 97
    Digitale Medien
    Digitale Medien
    Field bioassay ofexo- andendo-brevicomin withDendroctonus ponderosae in lodgepole pine (1982)
    Springer
    Journal of chemical ecology 8 (1982), S. 701-707 
    Details
    ISSN: 1573-1561
    Schlagwort(e): Coleoptera ; Scolytidae ; Dendroctonus ponderosae ; pheromone ; exo-brevicomin ; endo-brevicomin ; Pinus contorta
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Abstract Bothexo- andendo-brevicomin reduced the response of flyingDendroctonus ponderosae (Coleoptera: Scolytidae) to an attractant composed oftrans-verbenol and terpenes or oftrans- andcis-verbenol and terpenes in a stand ofPinus contorta var.murrayana. These data suggest that racemicexo- andendo-brevicomin may interrupt aggregation in populations of mountain pine beetle colonizing lodgepole pine; functions of the natural chiral compounds are unknown.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00988311
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 98
    Digitale Medien
    Digitale Medien
    Correlated response to phototactic selection (1984)
    Springer
    Behavior genetics 14 (1984), S. 279-293 
    Details
    ISSN: 1573-3297
    Schlagwort(e): phototaxis ; Drosophila ; correlated response ; selection ; sepia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract Artificial selection for positive and negative phototaxis was conducted in populations ofDrosophila melanogaster that were polymorphic at thesepia locus. Photoselection response was accompanied by a correlated response in the frequency of thesepia allele. Changes insepia frequency were shown to be significantly different from those predicted by several neutral models. Implications of this correlated response are briefly discussed in terms of the neurogenetic basis of phototaxis.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01065547
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 99
    Digitale Medien
    Digitale Medien
    A note on barometric pressure and behavior inDrosophila pseudoobscura (1984)
    Springer
    Behavior genetics 14 (1984), S. 315-317 
    Details
    ISSN: 1573-3297
    Schlagwort(e): Drosophila ; mating and barometric pressure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Notizen: Abstract During a study ofDrosophila mating behavior we observed unexpected changes in performance under ostensibly identical experimental conditions. We related the behavior during the 17 days of the experiment to changes in ambient humidity and barometric pressure. Humidity had no significant effect, but reduced barometric pressure was found to be associated with reduced mating activity (R 2=0.29,P〈0.025), accounting for close to 30% of the variation in total number of matings.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01065549
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 100
    Digitale Medien
    Digitale Medien
    Genetic elements of courtship inDrosophila: Mosaics and learning mutants (1984)
    Springer
    Behavior genetics 14 (1984), S. 383-410 
    Details
    ISSN: 1573-3297
    Schlagwort(e): Drosophila ; courtship ; learning ; circadian
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Psychologie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF01065442
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...