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Investigates the emergence of the concept of transaction costs in modern economics. Controversial issues closely related to the emergence of the concept of transaction costs; Interpretations of particular aspects of the concept; Authors who have helped the concept gains its prominence.

The diagnosis and treatment of irritable bowel syndrome (IBS) are complicated. Artichoke extracts are well known to be helpful in various gastrointestinal disorders. A hydrophilic extract 36_U mainly containing luteolin-7-glycoside, luteolin-7-O-glucoside, small amounts of cynarin and luteolin increased contraction of rat ileum. This is mainly mediated by 5-HT[3] -- and 5-HT[2] receptors but not 5-HT[4] receptors as can be derived by using specific antagonists such as tropisetrone, GR113806 and ketanserine. Additional mechanisms (receptors) are involved since the combination of these three antagonists was not able to fully prevent the contractive effect of extract 36_U. The lipophilic extract 36_EB mainly containing cynarin, luteolin including its glycosides, and cholorogenic acid in contrast to extract 36_U had a relaxing effect which could hardly be washed out. It was diminishing a serotonin effect and was not modified by ACh or substance P. The peristaltic threshold, i.e. the distension necessary for inducing a pathophysiologically relevant propulsion activity, is one of the important features being correlated with IBS. The peristaltic threshold was decreased by both serotonin and extract U_36. From the data it can be derived that the extract 36_U may be useful in IBS combined with obstipation when gastrointestinal contraction is necessary, whereas 36_EB may be useful in IBS combined with diarrhea when gastrointestinal relaxation is desired. Especially interesting are the influence on the threshold. It would be interesting to know which effects are mediated via cynarin and luteolin or its glycosides. [ABSTRACT FROM AUTHOR]

•Funding for renewables has been cut across Europe in the years since the financial crisis.•Crowdfunding models share a societal ethos with proponents of investment in renewables.•Positive attitudes are shown to be widespread regarding crowdfunding's potential to support renewables.•The evidence suggests that both emotional and pragmatic (experiential) factors underpin this pattern., Competing Interests: None., (© 2020 Elsevier B.V. All rights reserved.)

Mature seeds of 20 Linum species were analyzed for their content of lignans. The seeds of common flax (Linum usitatissimum L.) are known to contain as characteristic lignan sesoisolariciresinol diglucoside (SDG), whose presence in seeds of some other Linum species has also been reported. In order to investigate the material for the presence of such very polar lignans as well as for less polar non-glycosidic lignans as frequently found in aerial parts of Linum species, polar and non-polar extracts of each sample were analyzed by HPLC/ESI-MSMS. SDG was detected in 15 of 16 investigated seed samples of taxa representing sections Linum and Dasylinum. None of eight samples of taxa from sections Syllinum and Linopsis contained detectable amounts of SDG. Quite interestingly, most of the SDG-positive samples contained the 8R,8'R-isomer exclusively while only three (including L. usitatissimum) contained the 8S,8'S-stereoisomer as the predominant form. As a most noteworthy finding, the dichloromethane extracts obtained from seeds of several Linum species were found to contain significant concentrations of non-polar cyclolignans of the arylnaphthalene/-dihydronaphthalene lactone type or, alternatively of the aryltetralin lactone type. Thus, seeds of Linum perenne L. as well as those of several other representatives of sections Linum and Dasylinum were found to contain significant concentrations of the arylnaphthalene justicidin B along with further compounds of this type and some aryldihydronaphthalene-type lignans. On the other hand, seeds of Linum flavum and further representatives of section Syllinum were found to contain aryltetralin-type lignans, mainly in the form of esters with aliphatic carboxylic acids, such as 6-methoxypodophyllotoxin-7-O-n-hexanoate, whose occurrence in L. flavum seeds has very recently been reported by us for the first time. Various chemosystematic and biogenetic aspects are discussed in the light of these results., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

In post-Sputnik America, when many policymakers and social scientists feared the Soviet Union had a technological advantage over the United States, assessing the relative importance of patents for inventive activity and examining whether scientific research constituted a public good were paramount concerns. The neoliberals of the University of Chicago and the planners of the Cowles Commission both spoke to these issues. This paper sheds light on their views on patents and public goods in the late 1950s and early 1960s by examining representatives of Cowles and Chicago, Kenneth Arrow and Ronald Coase, respectively. Furthermore, it evaluates whether their views on patents and public goods clashed with the interests of RAND, at which both Arrow and Coase worked at some point during this time period. The paper argues that the Chicago-neoliberal position of Coase undermined the interests of RAND, while the Cowles-planning conclusions of Arrow furthered those interests., (© 2011 Wiley Periodicals, Inc.)

The aerial parts of 54 accessions representing 41 Linum species and four species of related genera were analysed for lignans by means of HPLC-ESI/MS-MS-UV/DAD. In total, 64 different lignans of the aryltetralin-, arylnaphthalene-, aryldihydronaphthalene-, dibenzylbutyrolactone-, and furofuran type were identified. According to their lignan profile, the Linum species can be divided in two groups accumulating as major lignan types either cyclolignans of the aryltetralin-series on one hand, or aryldihydronaphthalenes/arylnaphthalenes, on the other. Five of the investigated Linum species did not contain any detectable amounts of these lignans under the chosen analytical conditions. Furthermore, none of the lignans identified in Linum species was detectable in representatives of three related genera, namely, Reinwardtia (Linaceae, Linoideae), Hugonia and Indorouchera (Linaceae, Hugonioideae). The two species groups differing in the types of the dominating cyclolignans comprise representatives of the major taxonomic sections. Representatives of sections Syllinum, Cathartolinum and Linopsis accumulate mainly aryltetralins while those of sections Linum and Dasylinum were found to contain mainly aryldihydronaphthalenes/-naphthalenes. These phytochemical data correlate very well with a recent study on the molecular phylogeny of Linum/Linaceae, where a subdivision of Linum into two major clades comprising representatives of the two mentioned groups was found. Thus, the distribution of lignans apparently reflecting phylogenetic interrelations at the infrageneric level, a plausible scenario for the evolution of lignan biosynthesis in the genus Linum can now be presented., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The conformations of inherently chiral resorc[4]arenes were studied by circular dichroism (CD) spectroscopy. Whereas in aprotic solvents the crown conformation (C4) is preferred, protic solvents favor the boat conformation (C2). As a result of electronic coupling of the lowest L(b) state of the resorcinol unit in the resorc[4]arene, the CD spectra show a strong dependence on the conformation of the macrocycle. For the first time the solvent dependence of the CD spectra was qualitatively analyzed and simulated by using theoretical methods. We have thus demonstrated not only that the conformation of the calixarene is dramatically manipulated by the solvent but also that the joint use of chiroptical measurements and theoretical calculations is a powerful and versatile tool for elucidating structural variations in supramolecular chemistry.

The interaction of inherently chiral resorc[4]arenes with different chiral ammonium ions was measured by ESI-MS. For that purpose one enantiomer of the ammonium guests was labeled with deuterium to distinguish the enantiomers by their mass. We synthesized the ammonium salts by reaction of chiral primary amines with either CH3I or CD3I and analyzed the resulting ammonium iodides by NMR and optical rotation. The complexation experiments were performed by mixing the chiral host with various ratios of the unlabeled guest and its labeled enantiomer. By analysis of the integrals of the host-guest complexes we observed a chiral discrimination effect and a secondary isotope effect as well.