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81.
Matthias Otto Müller Stefan N. Groesser Silvia Ulli-Beer 《European Journal of Operational Research》2012,216(2):495-502
Collaborative research, defined as research involving actors participating in the problem situation under study, has an important role in operational research, strategic management and systems thinking. In a recent study, we found that a strong organizational focus incorporated into many soft operational research (OR) approaches is inadequate for studying societal problem situations, which are fragmented and have no clear boundary. Specifically, we failed to find a process of identifying individuals that is capable of representing the perspectives of actors and sufficient for research into societal problem situations. We found no clear terminology accounting for ontological differences between actors, individuals representing them and conceptual representations of acting entities. In response to this gap in the literature, we propose terminology that differentiates among actors (individuals or collective entities in the real world), experts (individuals capable of representing the perspective of an actor) and agents (ideal-typical representations of actors). Based on this terminology, we propose an iterative method to guide the assembly of an expert group to undertake collaborative research into societal problem situations. To demonstrate the application of our method, we present selected insights from our study in an electronic supplement. 相似文献
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Inmaculada Robina Silvia Gómez-Bujedo José G. Fernández-Bolaños José Fuentes 《合成通讯》2013,43(13):2379-2397
To prepare C-sulfonate derivatives of disaccharides two different strategies were followed. Thus 6- and 6′-C-sulfocellobiosides 4 and 10–12 were prepared starting from a suitably protected cellobioside. The 6′-C-sulfoaminocellobioside 18 was prepared by construction of the molecule through a glycosylation reaction. In both cases, the synthetic pathway involves regioselective tosylation, introduction of a sulfur atom by nucleophilic displacement with potassium thioacetate and oxidation with hydrogen peroxide. 相似文献
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Elionai Cassiana de Lima Gomes Izabella Ercole de Carvalho Silvia Ligório Fialho Jamile Barbosa Maria Irene Yoshida Armando da Silva Cunha Júnior 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2123-2128
Most of the pharmaceutical products are formulated as solid dosage form, which may present drug–excipient interactions that lead to changes in the chemical nature of the drug, such as solubility and bioavailability and may compromise its safety and effectiveness. Differential scanning calorimetry (DSC) is a widely used method for the rapid evaluation of the drug-excipient compatibility and the stability of the mixture formed; however, there is no consensus on the preparation methods of the drug–excipient mixtures. The aim of this study was to investigate the influence of the mixing method on the drug–excipient compatibility studies by means of DSC analysis, using tenofovir disoproxil fumarate as a drug model. Statistical analysis revealed significant differences in the heat of fusion of the drug in the mixtures prepared by several mixing methods. Vortex Mixer with a Pop-Off Cup used for 3 min proved to be very satisfactory for these studies. A polymorphic transition was observed in the mixture prepared with the mortar and pestle. Therefore, this method should be avoided since it may induce errors in the interpretation of DSC results. In this way, the mixing method used to prepare a mixture for studies of interactions between the API and the excipients in a pharmaceutical formulation has a great influence on the results and it must be chosen carefully. 相似文献
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Roberta Seraglia Giovanni Sartore Raffaella Marin Silvia Burlina Enzo Manzato Eugenio Ragazzi Pietro Traldi Annunziata Lapolla 《Journal of mass spectrometry : JMS》2013,48(1):105-110
Increased oxidation of low density lipoprotein (LDL) is characteristic of atherosclerosis. In this frame, high density lipoproteins (HDL) play an important role, being able to remove lipid peroxides (LPOs) and cholesterol from oxidized LDL, so exhibiting a protective role against atherosclerosis. A wide range of reactive compounds lead to the oxidation of methionine (Met) residues with the formation of methionine sulphoxide (MetO) in apolipoprotein A‐I (ApoA‐I). Consequently, the determination of MetO level can give both an evaluation of oxidative stress and the reduced capability of ApoA‐I in LPOs and cholesterol transport. For these reasons, the development of analytical methods able to determine the MetO level is surely of interest, and we report here the results obtained by MALDI mass spectrometry. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献