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991.
Kinney CA Furlong ET Kolpin DW Burkhardt MR Zaugg SD Werner SL Bossio JP Benotti MJ 《Environmental science & technology》2008,42(6):1863-1870
Analysis of earthworms offers potential for assessing the transfer of organic anthropogenic waste indicators (AWIs) derived from land-applied biosolid or manure to biota. Earthworms and soil samples were collected from three Midwest agricultural fields to measure the presence and potential for transfer of 77 AWIs from land-applied biosolids and livestock manure to earthworms. The sites consisted of a soybean field with no amendments of human or livestock waste (Site 1), a soybean field amended with biosolids from a municipal wastewater treatment plant (Site 2), and a cornfield amended with swine manure (Site 3). The biosolid applied to Site 2 contained a diverse composition of 28 AWls, reflecting the presence of human-use compounds. The swine manure contained 12 AWls, and was dominated by biogenic sterols. Soil and earthworm samples were collected in the spring (about30 days after soil amendment) and fall (140-155 days after soil amendment) at all field sites. Soils from Site 1 contained 21 AWIs and soil from Sites 2 and 3 contained 19 AWls. The AWI profiles at Sites 2 and 3 generally reflected the relative composition of AWls present in waste material applied. There were 20 AWls detected in earthworms from Site 1 (three compounds exceeding concentrations of 1000 microg/kg), 25 AWls in earthworms from Site 2 (seven compounds exceeding concentrations of 1000 microg/ kg), and 21 AWls in earthworms from Site 3 (five compounds exceeding concentrations of 1000 microg/kg). A number of compounds thatwere present in the earthworm tissue were at concentrations less than reporting levels in the corresponding soil samples. The AWIs detected in earthworm tissue from the three field sites included pharmaceuticals, synthetic fragrances, detergent metabolites, polycyclic aromatic hydrocarbons (PAHs), biogenic sterols, disinfectants, and pesticides, reflecting a wide range of physicochemical properties. For those contaminants detected in earthworm tissue and soil, bioaccumulation factors (BAF) ranged from 0.05 (galaxolide) to 27 (triclosan). This study documents that when AWls are present in source materials that are land applied, such as biosolids and swine manure, AWls can be transferred to earthworms. 相似文献
992.
Peter Schieberle Werner Grosch 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1994,198(4):292-296
Aroma extract dilution analyses revealed twenty-eight odorants in fresh rye bread crust and twenty in its crumb. On the basis of high flavour dilution factors, methional (boiled potato), 3-methylbutanal (malty), (E)-2-nonenal (green, tallowy), (E,E)-2,4-decadienal (fatty) and acetic acid (sour, pungent) belonged to the potent odorants of the crust, and phenylacetaldehyde, (E)-2-nonenal and (E,E)-2,4-decadienal to those of the crumb. Compared with the crust, especially the odour activities of methional, 3-methylbutanal, 2-ethyl-3,5-dimethyl-pyrazine and 4-hydroxy-2,5-dimethyl-3(2H)-furanone were significantly lower in the crumb. Calculation of the odour activity values (OAV; ratio of concentration to odour threshold) indicated that the higher OAV of methional in the rye crust and the higher OAV of 2-acetyl-1-pyrroline in the wheat bread crust mainly contributed to the flavour difference of the two kinds of bread.
Wichtige Geruchsstoffe der Roggenbrotkruste-Unterschiede zur Krume sowie zur Weißbrotkruste
Zusammenfassung Aromaextraktverdünnungsanalysen ergaben 28 Geruchsstoffe in frischer Roggenbrotkruste und 20 in der Krume. Aufgrund hoher FD-Faktoren gehörten Methional (gekochte Kartoffel), 3-Methylbutanal (malzartig), (E)-2-Nonenal (grün, talgig), (E,E)-2,4-De-cadienal (fettig) und Essigsäure (sauer, stechend) zu den potenten Geruchsstoffen der Kruste sowie Phenylacetal-dehyd, (E)-2-Nonenal und (E,E)-2,4-Decadienal zu denen der Krume. Im Vergleich zur Kruste waren insbesondere die Geruchsaktivitäten von Methional, 3-Methylbutanal, 2-Ethyl-3,5-dimethylpyrazin und 4-Hydroxy-2,5-dimethyl-3 (2H)-furanon in der Krume deutlich erniedrigt.-Die Berechnung von Aromawerten (Quotient aus Konzentration und Geruchsschwelle) zeigte, daß insbesondere der erheblich höhere Aromawert des Methionals in der Roggenbrotkruste und der des röstig, süß riechenden 2-Acetyl-1-pyrrolins in der Weißbrotkruste wesentlich zum Aromaunterschied beider Brotarten beiträgt.相似文献
993.
Imre Blank Karl-Heinz Fischer Werner Grosch 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(5):426-433
Summary Aroma extract dilution analysis of linden honey volatiles resulted in 21 odour compounds having high factors of dilution (FD); 18 of these compounds were identified as 1-hexen-3-one, 2-acetyl-1 -pyrroline, dimethyl trisulphide, methional, phenylacetaldehyde, 2-phenylethanol, linalool, p-cresol, 3,9-epoxy-lpmenthene, 4-methylacetophenone, 3,9-epoxy-1,4(8)-p-menthadiene (linden ether), 1,3 p-menthadien-7-al, p-anisaldehyde, 4vinylguaiacol, (E)-p-damascenone, eugenol, vanillin andcis-rose oxide. Linden ether andcis-rose oxide, which were also found in an extract obtained from the blossoms of the lime tree (Tifa cordata), were absent in honeys of other botanical origin. These two odourants and the odourlesstrans-limonene-1,2-diol are proposed as indicators for linden honey. The odour thresholds (in air) of the 18 aroma compounds are reported.
Intensive neutrale Geruchsstoffe von Lindenhonig. Unterschiede zu Honigen anderer botanischer Herkunft
Zusammenfassung Die Aromaextrakt-Verdünnungs-analyse der flüchtigen Verbindungen aus Lindenhonig ergab 21 Geruchsstoffe mit hohen FD-Faktoren; 18 davon wurden identifiziert: l-Hexen-3-on, 2-Acetyl-1 -pyrrolin, Dimethyltrisulfid, Methional, Phenylacetaldehyd, 2-Phenylethanol, Linalool, p-Kresol, 3,9-Epoxy-1 p-menthen, 4-Methylacetophenon, 3,9-Epoxy-1,4(8)p-menthadien (Lindenether), 1,3 -p-Menthadi-en-7-al,p-Anisaldehyd, 4-Vinylguajacol, (E)--Da-mascenon, Eugenol, Vanillin undcis-Rosenoxid. Lindenether undcis-Rosenoxid, die auch in einem Extrakt von Lindenblüten (Tilla cordata) vorkamen, fehlten in Honigen anderer botanischer Herkunft. Diese beiden Aromastoffe und das geruchlosetrans-Limonen-1,2-diol werden als Indikatoren für Linden honig vorgeschlagen. Die Geruchsschwellen (in Luft) der 18 Aromastoffe wurden bestimmt.相似文献
994.
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997.
Dr. Halina M. Werner Samuel K. Estabrooks Dr. G. Michael Preston Prof. Dr. Jeffrey L. Brodsky Prof. Dr. W. Seth Horne 《Chembiochem : a European journal of chemical biology》2019,20(18):2346-2350
Ubiquitin (Ub) plays critical roles in myriad protein degradation and signaling networks in the cell. We report herein Ub mimetics based on backbones that blend natural and artificial amino acid units. The variants were prepared by a modular route based on native chemical ligation. Biological assays show that some are enzymatically polymerized onto protein substrates, and that the resulting Ub tags are recognized for downstream pathways. These results advance the size and complexity of folded proteins mimicked by artificial backbones and expand the functional scope of such agents. 相似文献
998.
Dr. Brian Budke Dr. Werner Tueckmantel Dr. Kelsey Miles Dr. Alan P. Kozikowski Prof. Philip P. Connell 《ChemMedChem》2019,14(10):1031-1040
RAD51 is the central protein in homologous recombination (HR) repair, where it first binds ssDNA and then catalyzes strand invasion via a D-loop intermediate. Additionally, RAD51 plays a role in faithful DNA replication by protecting stalled replication forks; this requires RAD51 to bind DNA but may not require the strand invasion activity of RAD51. We previously described a small-molecule inhibitor of RAD51 named RI(dl)-2 (RAD51 inhibitor of D-loop formation #2, hereafter called 2 h ), which inhibits D-loop activity while sparing ssDNA binding. However, 2 h is limited in its ability to inhibit HR in vivo, preventing only about 50 % of total HR events in cells. We sought to improve upon this by performing a structure–activity relationship (SAR) campaign for more potent analogues of 2 h . Most compounds were prepared from 1-(2-aminophenyl)pyrroles by forming the quinoxaline moiety either by condensation with aldehydes, then dehydrogenation of the resulting 4,5-dihydro intermediates, or by condensation with N,N′-carbonyldiimidazole, chlorination, and installation of the 4-substituent through Suzuki–Miyaura coupling. Many analogues exhibited enhanced activity against human RAD51, but in several of these compounds the increased inhibition was due to the introduction of dsDNA intercalation activity. We developed a sensitive assay to measure dsDNA intercalation, and identified two analogues of 2 h that promote complete HR inhibition in cells while exerting minimal intercalation activity. 相似文献
999.
Gunde MK Krasovec UO Platzer WJ 《Journal of the Optical Society of America. A, Optics, image science, and vision》2005,22(3):416-423
Switchable windows are being installed into modern buildings. We report on how the variable transmittance of gasochromic and electrochromic switchable windows changes the color rendering properties of the daylight passing through these windows. We present a series of color rendering examples. Correlated color temperature and color rendering indices are insufficient to describe the color properties of this filtered light, as these indices are beyond the applicability limits. We obtain more reliable results using the color shifts (deltaE) of different objects. We find that as the transmittance of the window changes, each surface color moves along a path of the CIELAB space in the same direction for both switchable units. The direction and distance moved differs among test-color samples. The appearance of an array of colored objects is strongly distorted at higher coloration states of the windows. 相似文献
1000.
Marion Fischer Claudia Sperling Carsten Werner 《Journal of materials science. Materials in medicine》2010,21(3):931-937
Biomaterial induced coagulation encompasses plasmatic and cellular processes. The functional loss of biomedical devices possibly
resulting from these thrombotic reactions motivates the need for a better understanding of processes occurring at blood–biomaterial
interfaces. Well defined model surfaces providing specific chemical–physical properties (self assembled monolayers (SAMs))
displaying hydrophobic or/and acidic terminal groups were used to uncover initial mechanisms of biomaterial induced coagulation.
We investigated the influence of electrical charge and wettability on platelet- and contact activation, the two main actors
of blood coagulation, which are often considered as separate mechanisms in biomaterials research. Our results show a dependence
of contact activation on acidic surface groups and a correlation of platelet adhesion to surface hydrophobicity. Clot formation
resulting from the interplay of blood platelets and contact activation was only found on surfaces combining both acidic and
hydrophobic surface groups but not on monolayers displaying extreme hydrophobic/acidic properties. 相似文献