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Blockchain technology is generating interest in novel applicative fields such as co-production of public services. Our CommonsHood project is a “wallet app” that uses the Blockchain as a tool to support sustainability of the local economy. Its tokenization mechanism allows everyone to create new types of cryptographic tokens on the Blockchain in order to digitalize assets, augment the availability of local liquidity, and incentivize cooperative socio-economic interactions. This article analyzes a concrete application of CommonsHood for innovating local development policies and service co-production in the tourism sector. We examine this application using Linders’s analytical framework for information and communications technology (ICT)-enabled co-production of services (2012). We show the advantages our project brings for local policies on tourism development, and we discuss the benefits and costs of using the Blockchain in that context. We argue that the observed case study covers different types of digitally enabled co-production of services, and that it can be defined as a case of Governance as a Platform. We also argue that well-established analytical frameworks for ICT-enabled co-production of services need to be expanded in order to account for the new affordances enabled by the Blockchain technology, namely the creation and transaction of digital values, which represent a paradigm change in how we understand the Internet and digital co-production.

Can. J. Chem. 67, 1599 (1989. An accurate and simple method is proposed for the determination of sulfanilic acid in the presence of sulfonamides. This method is based on measuring the intensity of the red colour that develops when sulfanilic acid is allowed to react with potassium 1.2-naphthoquinone-4-sulphonate (NS) in a chloroaceticchloroacetate buffer at pH 3.4. Colour development reaches completion after 2 h, allowing sulfanilic acid to be quantified spectrophotometrically at 470 nm (E = 4.7 X lo3 L mol-' cm-I). The main product causing colour formation, potassium 1,2-naphthoquinone-4-(N-aminophenylen-4-sulphonate) (NSSA), was isolated and characterized. When samples also contain sulfonarnides an extraction into chloroform must be performed. Sulfanilic acid in binary mixtures with sulfanilamide, sulfacetamide, or sulfathiazole can be determined either by direct measurement of the aqueous phase after extraction at 470 nm or by subtracting from the absorbance of the aqueous phase before extraction the absorbance of sulfonamide as determined by measuring the extracted chloroform phase at 345 nm. Sulfadiazine, sulfamethoxipyridazine, and sulfamethoxazole interferences are prevented by their extraction into chloroform at pH 7.2; these species cannot be determined. The effects of pH, reagent concentration, time, and temperature on colour formation were investigated. In all cases the standard addition method gave more accurate results. The method was applied to several pharmaceutical samples.Key words: spectrophotometry, sulfanilic acid, sulfonamides, potassium 1,2-naphthoquinone-4-sulphonate.A. PUNTA CORDERO, F. J. BARRAGAN DE LA ROSA et A. GUIRAUM. Can. J. Chem. 67,1599 (1989. On propose une mCthode precise et simple pour dtterminer I'acide sulfanilique en prCsence de sulfonamides. La mCthode est basCe sur la mesure de I'intensitt de la couleur rouge qui se dCveloppe lorsqu'on fait rkagir de l'acide sulfanilique avec le 1,2-naphtoquinone-4-sulfonate de potassium (NS) dans un tampon d'acide chloroacCtique-chloroacCtate, B un pH de 3,4. La couleur est complktement dtveloppCe aprks deux heures et I'on peut alors quantifier I'acide sulfanilique d'une faqon spectrophotomttrique 470 nm (E = 4,7 X lo3 L mol-' cm-'). On a isole et caractCrisC le produit principal responsable de la couleur, le 1,2-naphtoquinone-4-(N-aminophCnyl~ne-4-sulfonate) de potassium (NSSA). Lorsque les Cchantillons contiennent aussi des sulfonamides, on doit procCder B une extraction au chloroforme. L'acide sulfanilique en mClanges binaires avec la sulfanilamide, la sulfacCtamide ou le sulfathiazole peut &tre dCterminCe soit par une mesure directe de la phase aqueuse a 470 nm aprks extraction soit en soustrayant I'absorbance de la sulfonamide, telle que dCterminCe par une mesure a 345 nm de la phase chloroformique extraite, de l'absorbance de la phase aqueuse avant extraction. On peut prkvenir les interferences de la part de la sulfadiazine, de la sulfamCthoxipyridazine et du sulfamethoxazole en procCdant a leur extraction dans le chloroforme a un...

A detailed analysis of the cell recruitment and of the cell generation pattern of normal lymphocytes and chronic lymphatic leukaemia (CLL) lymphocytes, simulated by phytohaemagglutinin (PHA), was performed by the bromodi‐oxyuridine (BUdR) Hoechst technique. It was found that in normal cultures the majority of cells divide two or three times, producing an early peak of DNA synthesis, while only a few cells grow exponentially and pass through many rounds of replication. On the contrary, the majority of CLL responsive cells grow exponentially, producing a delayed peak of DNA synthesis, while cells which divide only two or three times are scarce or absent. No difference in the minimal cell cycle length of the normal and the CLL exponentially growing population was found. In addition, a cell population recruited into cycle for the first time 5–6 days following PHA stimulation was observed in normal cultures but not in CLL cultures.

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