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71.
How do individual politicians use the news media to reach their political goals? This study addresses the question by proposing an actor‐centered, functional approach. We distinguish 2 essential functions (and subfunctions) the mass media have for political elites. The media are a source of information; politicians depend on it for pure information and they can profit from the momentum generated by media information. The media also are an arena elites need access to in order to promote themselves and their issues. These 2 functions offer certain politicians a structural advantage over others and, hence, are relevant for the power struggle among political elites. A systematic functional account enables comparisons of the role of the media across politicians and political systems. 相似文献
72.
Dirk Jan van Drooge Kevin Braeckmans Wouter L. J. Hinrichs Katrien Remaut Stefaan C. De Smedt Henderik W. Frijlink 《Macromolecular rapid communications》2006,27(14):1149-1155
Summary: Efficient engineering of solid dispersions stagnates by the current inability to establish the mode of drug distribution on a molecular level at a low drug load. This study describes the application of fluorescence resonance energy transfer (FRET) to characterize the mode of incorporation of dispersed lipophilic molecules in a solid matrix. Two different lipophilic fluorophores (donor and acceptor) were used as model substances and were incorporated in polyvinylpyrrolidone to form solid dispersions using two different production processes: lyophilization and fusion. The efficiency of the resonance energy transfer from donor to acceptor was measured by confocal microscopy. We show that the method can be used to compare the modes of drug incorporation of solid dispersions at the nanoscale.
73.
Viktor Jobbágy M. Teresa Crespo Raf Van Ammel Maria Marouli André Moens Stefaan Pommé Eduardo García-Toraño 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):345-352
In this paper the source preparation procedures for high-resolution 238U sources are described and compared. This work was done within collaboration between CIEMAT and IRMM in the frame of MetroFission, a project of the European Metrology Research Programme, in order to determine the alpha-emission probabilities of 238U. 238U was deposited from organic (iso-propanol) and inorganic-H2SO4/(NH4)2SO4, saturated NH4NO3-electrolyte solutions on metal backings. The parameters affecting electrodeposition were studied and optimized. The activity distribution of uranium was checked by autoradiography. Results show that the 238U source quality is significantly better using the saturated NH4NO3 than the two other electrolytes. By this method, sources of 18.6–22 mm diameter, 26 μg cm?2 surface density, ~15–18 keV resolution and a peak to valley ratio higher than 50 could be made. This reconciles the inherently opposing requirements of high resolution and sufficient count rate needed to determine the alpha–emission probabilities accurately. 相似文献
74.
75.
Wu B Szymański W Wijma HJ Crismaru CG de Wildeman S Poelarends GJ Feringa BL Janssen DB 《Chemical communications (Cambridge, England)》2010,46(43):8157-8159
By replacing a single active-site residue Cys107 with Ser in phenylalanine aminomutase (PAM), the enzyme gained tyrosine aminomutase (TAM) activity while retaining PAM activity and high enantioselectivity. This engineered enantioselective TAM also catalyzed formation of β-tyrosine from p-coumaric acid and may prove to be useful for the synthesis of enantiopure β-tyrosine and its derivatives. 相似文献
76.
77.
De Geest BG Willart MA Lambrecht BN Pollard C Vervaet C Remon JP Grooten J De Koker S 《Angewandte Chemie (International ed. in English)》2012,51(16):3862-3866
Immunizing: to evoke highly potent immune responses against recombinant antigens, hollow capsules consisting of layers of dextran sulphate and poly-L-arginine that encapsulate the antigen ovalbumin (orange circles) were coated with immune-activating CpG-containing oligonucleotides (green). These capsules were readily internalized by dendritic cells and showed activity in further immunization experiments. 相似文献
78.
M. Sc. Hendrik Naatz Dr. Bella B. Manshian Dr. Carla Rios Luci Dr. Vasiliki Tsikourkitoudi Prof. Dr. Yiannis Deligiannakis Dr. Johannes Birkenstock Dr. Suman Pokhrel Prof. Dr. Lutz Mädler Dr. Stefaan J. Soenen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(5):1844-1852
The progress in nanomedicine (NM) using nanoparticles (NPs) is mainly based on drug carriers for the delivery of classical chemotherapeutics. As low NM delivery rates limit therapeutic efficacy, an entirely different approach was investigated. A homologous series of engineered CuO NPs was designed for dual purposes (carrier and drug) with a direct chemical composition–biological functionality relationship. Model-based dissolution kinetics of CuO NPs in the cellular interior at post-exposure conditions were controlled through Fe-doping for intra/extra cellular Cu2+ and biological outcome. Through controlled ion release and reactions taking place in the cellular interior, tumors could be treated selectively, in vitro and in vivo. Locally administered NPs enabled tumor cells apoptosis and stimulated systemic anti-cancer immune responses. We clearly show therapeutic effects without tumor cells relapse post-treatment with 6 % Fe-doped CuO NPs combined with myeloid-derived suppressor cell silencing. 相似文献
79.
Stefaan Vaes 《Journal of Functional Analysis》2005,229(2):317-374
Given a closed quantum subgroup of a locally compact quantum group, we study induction of unitary corepresentations of the quantum subgroup to the ambient quantum group. More generally, we study induction given a coaction of the quantum subgroup on a C*-algebra. We prove imprimitivity theorems that unify the existing theorems for actions and coactions of groups. This means that we define quantum homogeneous spaces as C*-algebras and that we prove Morita equivalence of crossed products and homogeneous spaces. We essentially use von Neumann algebraic techniques to prove these Morita equivalences between C*-algebras. 相似文献
80.
Reaction of 2-benzyl-5-halopyridazin-3(2H)-ones (3) with Grignard reagents followed by quenching with electrophiles unexpectedly yielded 4,5-disubstituted pyridazin-3(2H)-ones instead of 5-substituted pyridazin-3(2H)-ones. These reactions represent the first examples of cine substitution in which the anionic σ(H)-adduct is quenched by electrophiles (other than a proton) before elimination takes place. Insight into the reaction mechanism led to the direct transformation of 2-benzylpyridazin-3(2H)-one (7) and 2-benzyl-6-chloropyridazin-3(2H)-one (9) into the corresponding C-4 alkyl and aryl derivatives (when Br(2) was used as the electrophile). 相似文献