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111.
112.
Nijland HA Hartemink S van Kamp I van Wee B 《The Journal of the Acoustical Society of America》2007,122(3):1595
People move to another house for different reasons. It is sometimes presumed that a process of self-selection might take place on the basis of noise sensitivity, i.e., sensitive people would either leave high noise areas or not move into these areas in the first place. Thus, a "survivor population" would remain in the high noise areas. This research aims to investigate whether such a process can be observed in the Netherlands. The study does not show evidence of a process of self-selection based on noise sensitivity. Nevertheless, the results suggest that noise-sensitive people are less satisfied with their living environment and are more willing to move than those who are not noise sensitive. Due to the limited sample size, external validity is limited. 相似文献
113.
A simple numerical treatment of the infinite boundary in the BEM analysis of two-dimensional wave propagation problems in elastic half-spaces is proposed to avoid the spurious reflections of non-decaying Rayleigh waves introduced by the truncation of the boundary. The proposed method exploits the knowledge of the far-field asymptotic behavior of the solution to adequately correct the BEM displacement system matrix for the truncated problem to account for the contribution of the omitted part of the boundary. The reciprocal theorem of elastodynamics is used for a convenient computation of this contribution exclusively in terms of the boundary integrals of the original BEM system. The method is applied to the study of the acoustic emission from nucleating and propagating surface-breaking and buried cracks in a two-dimensional elastic half-space. It is shown to be particularly advantageous since it allows for an accurate calculation of the generated signal even when the observation point is located far from the acoustic emission source. 相似文献
114.
Production of the Bengamide Class of Marine Natural Products in Myxobacteria: Biosynthesis and Structure–Activity Relationships 下载免费PDF全文
Dr. Silke C. Wenzel Dr. Holger Hoffmann Dr. Jidong Zhang Dr. Laurent Debussche Dr. Sabine Haag‐Richter Dr. Michael Kurz Dr. Frederico Nardi Dr. Peer Lukat Irene Kochems Dr. Heiko Tietgen Prof. Dr. Dietmar Schummer Jean‐Paul Nicolas Dr. Loreley Calvet Dr. Valerie Czepczor Dr. Patricia Vrignaud Dr. Agnes Mühlenweg Priv.‐Doz. Dr. Stefan Pelzer Prof. Dr. Rolf Müller Prof. Dr. Mark Brönstrup 《Angewandte Chemie (International ed. in English)》2015,54(51):15560-15564
The bengamides, sponge‐derived natural products that have been characterized as inhibitors of methionine aminopeptidases (MetAPs), have been intensively investigated as anticancer compounds. We embarked on a multidisciplinary project to supply bengamides by fermentation of the terrestrial myxobacterium M. virescens, decipher their biosynthesis, and optimize their properties as drug leads. The characterization of the biosynthetic pathway revealed that bacterial resistance to bengamides is conferred by Leu 154 of the myxobacterial MetAP protein, and enabled transfer of the entire gene cluster into the more suitable production host M. xanthus DK1622. A combination of semisynthesis of microbially derived bengamides and total synthesis resulted in an optimized derivative that combined high cellular potency in the nanomolar range with high metabolic stability, which translated to an improved half‐life in mice and antitumor efficacy in a melanoma mouse model. 相似文献
115.
Irene Felker Gabriele Pupo Dr. Philip Kraft Prof. Dr. Benjamin List 《Angewandte Chemie (International ed. in English)》2015,54(6):1960-1964
Novel Cashmeran odorants were designed by molecular modeling. Their short syntheses involve a novel asymmetric Brønsted acid catalyzed Michael addition of unactivated α‐substituted ketones. This key transformation was realized by utilizing a new type of enol activation catalysis and affords different cyclic ketones bearing α‐quaternary stereocenters in good to excellent yields and with high enantioselectivity. Subsequent McMurry coupling and Saegusa–Ito oxidation furnished the enantiopure target odorants, one enantiomer of which indeed possesses the typical olfactory aspects of Cashmeran. 相似文献
116.
Direct Catalytic Enantio‐ and Diastereoselective Ketone Aldol Reactions of Isocyanoacetates 下载免费PDF全文
Dr. Raquel de la Campa Dr. Irene Ortín Prof. Dr. Darren J. Dixon 《Angewandte Chemie (International ed. in English)》2015,54(16):4895-4898
A catalytic asymmetric aldol addition/cyclization reaction of unactivated ketones with isocyanoacetate pronucleophiles has been developed. A quinine‐derived aminophosphine precatalyst and silver oxide were found to be an effective binary catalyst system and promoted the reaction to afford chiral oxazolines possessing a fully substituted stereocenter with good diastereoselectivities and excellent enantioselectivities. 相似文献
117.
118.
Silke C. Wenzel Holger Hoffmann Jidong Zhang Laurent Debussche Sabine Haag‐Richter Michael Kurz Frederico Nardi Peer Lukat Irene Kochems Heiko Tietgen Dietmar Schummer Jean‐Paul Nicolas Loreley Calvet Valerie Czepczor Patricia Vrignaud Agnes Mühlenweg Stefan Pelzer Rolf Müller Mark Brnstrup 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(51):15781-15785
119.
Supercritical fluid extraction (SFE) is a green alternative method of extraction for neutral lipids in seeds compared to conventional methods utilizing organic solvents. In this work, a novel method where SFE is hyphenated with an evaporative light scattering detector is presented. The method was subsequently applied to determine lipid content in crushed linseed. The new method enables rapid quantification of extracted lipids as well as be ability to continuously monitor the extraction rate in real-time, thus being able to determine the time point of completed extraction. 相似文献
120.
Antiviral Activity of Synthetic Aminopyrrolic Carbohydrate Binding Agents: Targeting the Glycans of Viral gp120 to Inhibit HIV Entry 下载免费PDF全文
Dr. Oscar Francesconi Prof. Cristina Nativi Dr. Gabriele Gabrielli Irene De Simone Sam Noppen Prof. Jan Balzarini Prof. Sandra Liekens Dr. Stefano Roelens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(28):10089-10093
The binding abilities of a set of structurally related aminopyrrolic synthetic receptors for mannosides, endowed with antimycotic activity against yeast and yeast‐like pathogens bearing mannoproteins on their cell surface, have been investigated towards the highly mannosylated gp120 and gp41 glycoproteins of the HIV envelope. A pronounced binding interaction with both glycoproteins was observed by SPR for most of the investigated compounds. Comparison of their binding properties towards the glycoproteins with their binding affinities toward mannosides revealed a direct correlation, supporting their role as carbohydrate binding agents (CBAs). Cytostatic activity studies revealed antiproliferative activity dependent on the nature and the structure of compounds. Antiviral activity studies against a broad panel of DNA and RNA viruses showed inhibitory effect against HIV infection of the T‐lymphocyte CEM cell line for two compounds, suggesting antiviral activity similar to other CBAs, such as the nonpeptidic pradimicin antibiotics. 相似文献