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61.
Robert Wegener Stefan Schulz Torsten Meiners Katja Hadwich Monika Hilker 《Journal of chemical ecology》2001,27(3):499-515
Egg deposition of the elm leaf beetle Xanthogaleruca luteola causes the emission of volatiles from its food plant, Ulmus minor. These volatiles are exploited by the egg parasitoid, Oomyzus gallerucae, to locate its host. In contrast to other tritrophic systems, the release of volatiles is not induced by feeding but by egg deposition. Previous investigations showed that the release is systemic and can be triggered by jasmonic acid. Comparison of headspace analysis revealed similarities in the blend of volatiles emitted following egg deposition and feeding. The mixture consists of more than 40 compounds; most of the substances are terpenoids. Leaves next to those carrying eggs emit fewer compounds. When treated with jasmonic acid, leaves emit a blend that consists almost exclusively of terpenoids. Dichloromethane extracts of leaves treated with jasmonic acid were also investigated. After separation of extracts of jasmonate induced elm leaves on silica, we obtained a fraction of terpenoid hydrocarbons that was attractive to the parasitoids. This indicates that jasmonic acid stimulates the production of terpenoid hydrocarbons that convey information of egg deposition to the parasitoid. 相似文献
62.
63.
Werner Henning und Karl Herrmann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1980,171(2):111-118
Zusammenfassung Blätter wie Früchte von 6 SortenPrunus domestica-Pflaumen enthalten hauptsächlich 3-Rutinoside, in geringerer Konzentration 3-Glucoside und 3-Galaktoside von Kämpferol und Quercetin Bowie Quercetin-3-rhamnosid. Dagegen weisen Pflaumen vonPrunus salicina (2 untersuchte Sorten) Kämpferol-3,7-bisrhamnosid und Kämpferol-3-arabinosyl-7-rhamnosid als Hauptflavonole auf. Hierdurch ist eine Unterscheidung beider Arten leicht and sicher mög-lich. Weiterhin konnten inSalicina-Pflaumen Kämpfe-rol-3-rutinosid sowie Quercetin-3-rhamnosid, -xylosid,-glucosid, -galaktosid, --l-arabinofuranosid and -rutinosid, auch Quercetin-7-rhamnosid and Kämpferol-7-glucosid nachgewiesen werden.Die Gesamtgehalte an Flavonolglykosiden lagen bei den untersuchten Pflaumensorten vonPrunus domestica (P. salicina) bei 2500–3340 (7170, 10350) ppm in Blättern and 20–52 (8, 24) in Früchten, jeweils bezogen auf Frischgewicht.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
Flavonol glycosides of plums of the species Prunus domestica L. and Prunus salicina lindley12. Phenolics of fruits
Summary Leaves and fruits from 6 cultivars ofPrunus domestica plums contain mainly 3-rutinosides; in smaller concentrations the 3-glycosides and 3-galactosides of kaempferol and quercetin as well as quercetin-3-rhamnoside are present. On the other hand, in plums ofPrunus salicina (2 examined cultivars) main flavonols are kaempferol-3,7-bisrhamnoside and kaempferol-3arabinosyl-7-rhamnoside. Due to the difference in composition, differentiation of these species will be easy and reliable. Additionally kaempferol-3-rutinoside and quercetin-3-rhamnoside, -xyloside,-glucoside, -galactoside, --l-arabinofuranoside and-rutinoside, and also quercetin-7-rhamnoside and kaempferol-7-glucoside could be detected inP. salicina plums. The total content of flavonol glycosides in the investigated plums ofPrunus domestica (P. salicina) were based on fresh weight about 2500–3340 (7170, 10350) ppm in the leaves and 20–52 (8, 24) ppm in the fruits.
11. Mitt.: Henning W, Herrmann K (1980) Z Lebensm Unters Forsch 170:433–444
Auszug aus der Promotionsarbeit von W. Henning: Bestimmung der in Pflaumen, Kirschen, Pfirsichen and Aprikosen vorkommenden Flavonolglykoside unter Anwendung der Hochdruckflüssigkeitschromatographie. Diss. Univ. Hannover 1980 相似文献
64.
Dr. Simon J. A. Wiedemeyer Dr. Guojie Wu Dr. T. L. Phuong Pham Heike Lang-Henkel Benjamin Perez Urzua Prof. James C Whisstock Dr. Ruby H. P. Law Prof. Torsten Steinmetzer 《ChemMedChem》2023,18(6):e202200632
Two series of macrocyclic plasmin inhibitors with a C-terminal benzylamine group were synthesized. The substitution of the N-terminal phenylsulfonyl group of a previously described inhibitor provided two analogues with sub-nanomolar inhibition constants. Both compounds possess a high selectivity against all other tested trypsin-like serine proteases. Furthermore, a new approach was used to selectively introduce asymmetric linker segments. Two of these compounds inhibit plasmin with Ki values close to 2 nM. For the first time, four crystal structures of these macrocyclic inhibitors could be determined in complex with a Ser195Ala microplasmin mutant. The macrocyclic core segment of the inhibitors binds to the open active site of plasmin without any steric hindrance. This binding mode is incompatible with other trypsin-like serine proteases containing a sterically demanding 99-hairpin loop. The crystal structures obtained experimentally explain the excellent selectivity of this inhibitor type as previously hypothesized. 相似文献
65.
66.
R. Neher M. Herrmann O. Fabrichnaya D. Pavlyuchkov H.J. Seifert 《Journal of the European Ceramic Society》2013,33(13-14):2447-2455
The liquid phase formation in the system AlN–Al2O3–Y2O3 was investigated via differential thermal analysis (DTA) combined with thermogravimetry (TG). For this purpose 17 samples covering a broad composition area of the quasi-ternary system were densified and heat-treated to achieve the equilibrium state. Melting temperatures were determined by DTA. SEM, EDX and XRD were used to study the phase assemblages and microstructures formed. The results were compared with thermodynamic calculations. 相似文献
67.
Amir Jourak Vilnis Frishfelds T. Staffan Lundström Inga Herrmann Annelie Hedström 《American Institute of Chemical Engineers》2013,59(3):1002-1011
The longitudinal (DL) and transverse (DT) dispersion coefficients in two‐dimensional (2‐D) randomly packed beds of circular particles in a laminar flow regime are derived. A 2‐D discrete system of particles is divided into cells using modified Voronoi diagrams. The relationship between the variation of the stream function and the averaged vorticity is obtained from computational fluid dynamics (CFD) simulations. The whole flow pattern is then obtained by using the principle of energy dissipation rate minimization. The obtained values of DL agree well with 3‐D experimental data for all velocities investigated. At very high velocities, DT in 2‐D appears to be higher than 3‐D experimental data. In addition, the effects of particle‐size distributions, packing structure, and porosity on the DL and DT were studied. One result was that an increase in the width of the particle‐size distribution resulted in higher values of DL and DT at high velocities. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1002–1011, 2013 相似文献
68.
F.L. Leite L.G. Paterno C.E. Borato P.S.P. Herrmann O.N. Oliveira Jr L.H.C. Mattoso 《Polymer》2005,46(26):12503-12510
Nanostructured films of poly(o-ethoxyaniline) (POEA) were studied by atomic force microscopy (AFM), which indicated a globular morphology for films containing one or more layers of POEA. Consistent with the nucleation and growth model for the adsorption process, the mean roughness and fractal dimension were found to increase with the time of adsorption and with the number of POEA layers in the initial stages of adsorption, reached maximum values and then decreased after 10 min of adsorption or after deposition of five POEA layers. Such behavior has been explained in terms of the decrease in the film irregularities, with voids being filled with polymeric material leading to smoother surfaces. 相似文献
69.
J. -M. Herrmann 《Topics in Catalysis》2005,34(1-4):49-65
In the present paper, the basic fundamentals of photocatalysis are explained with the influence of the five main parameters which govern the kinetics: (i) mass of catalyst, (ii) wavelength, (iii) partial pression and/or concentrations of reactants, (iv) temperature (at a second degree) and (v) the radiant flux. The main types of photocatalytic reactions presently described (all performed at room temperature) concern (i) the selective mild oxidation of hydrocarbons, (ii) the hydrogen production and (iii) the total oxidation reactions of organics in presence of water. The last point constitutes the ensemble of the last recent developments in photocatalysis. Most of organic contaminants, including dangerous pesticides, can be easily totally degraded and mineralized.Dyes are also not only decolorized, but mineralized in colored aqueous effluents. The most abundant ones (the azo-dyes) have their azo-group(s) –N=N– decomposed into N2(g), which represents an ideal decontamination case.Photocatalytic engineering is under development, now using deposited titania in a fixed bed. Some (solar) photocatalytic pilot reactors and prototypes are described. The use of solar energy as a source of activating UV–A irradiation is described as a sub-discipline called helio-photocatalysis. 相似文献
70.
Ramona Erber Steffen Spoerl Andreas Mamilos Rosemarie Krupar Arndt Hartmann Matthias Ruebner Juergen Taxis Mareike Wittenberg Torsten E. Reichert Gerrit Spanier Silvia Spoerl 《International journal of molecular sciences》2022,23(1)
Oral cancer often presents with aggressive behavior and a high risk of recurrence and metastasis. For oral squamous cell carcinoma (OSCC), which is the most frequent histological subtype, therapy strategies include surgery, radiation therapy, chemotherapy, immune checkpoint inhibitors, and EGFR inhibitors. Recently, a Trop-2 antibody-drug conjugate (ADC) has been approved in the United States of America for the treatment of advanced triple-negative breast cancer. However, this ADC has also been tested in other solid tumors including head & neck squamous cell carcinoma. The prognostic impact of Trop-2 has already been reported for several cancers. We studied the prognostic influence of Trop-2 protein expression on OSCC patients’ survival. The cohort comprised n = 229 OSCC patients with available archived tumor tissue and corresponding non-neoplastic oral mucosa tissue. Using immunohistochemistry, we investigated Trop-2 expression in both the central and peripheral regions of each tumor and in corresponding non-neoplastic oral mucosa. In patients suffering from OSCC with combined high central and low peripheral Trop-2 expression, five-year overall survival (OS) was 41.2%, whereas 55.6% of OSCC patients who presented lower central and/or higher peripheral tumoral Trop-2 expression were alive after five years (p = 0.075). In multivariate Cox regression, the expression pattern of high central tumoral and lower peripheral Trop-2 expression was significantly correlated with impaired OS (HR = 1.802, 95%-CI: 1.134–2.864; p = 0.013) and recurrence-free survival (RFS) (HR = 1.633, 95%-CI: 1.042–2.560; p = 0.033), respectively, when adjusting for co-variables. Hence, Trop-2 may serve as an independent prognostic biomarker in OSCC. In subsequent studies, the pathophysiological meaning of downregulated Trop-2 expression in the OSCC periphery has to be analyzed. 相似文献