With schools and universities closing across Europe, the Covid-19 lockdown left actors in the field of education battling with the unprecedented challenge of finding a meaningful way to keep the wheels of education turning online. The sudden need for digital solutions across the field of education resulted in the emergence of a variety of digital networks and collaborative online platforms. In this joint article from scholars around Europe, we explore the Covid-19 lockdowns of physical education across the European region, and the different processes of emergency digitalization that followed in their wake. Spanning perspectives from Italy, Germany, Belgium, and the Nordic countries, the article’s five cases provide a glimpse of how these processes have at the same time accelerated and consolidated the involvement of various commercial and non-commercial actors in public education infrastructures. By gathering documentation, registering dynamics, and making intimations of the crisis as it unfolded, the aim of the joint paper is to provide an opportunity for considering the implications of these accelerations and consolidations for the heterogeneous futures of European education.

The thermoreversible gelation of solutions of syndiotactic poly(methyl methacrylate) in toluene has been studied by different experimental techniques. A combination of calorimetric, infrared, fluorescence, light scattering, and rheological observations supports the two-step gelation mechanism, proposed in a previous paper. A fast intramolecular conformational change is followed by an intermolecular association. The change in molecular mobility during the gelation process has been followed by NMR. Further support for the two-step mechanism has been found in the temperature dependence of the fluorescence properties of a probe covalently attached to the polymer chain. Finally, a concentration-temperature diagram for the polymer-solvent system has been constructed.

This paper discusses the constructivist, negotiated perspective to INGO accountability. According to this perspective, INGO accountability is a process of mutual negotiations between different INGO stakeholders who hold different accountability demands. Acknowledging that this perspective provides a good starting point for a better understanding of INGO accountability, we comment on this conceptualization of INGO accountability. Through an analysis of accountability instruments and procedures, we examine closely how the demands of the INGO's stakeholders are embedded in particular relationships of accountability which are sustained by particular accountability logics. From this analysis, we point out that, due to the differences that exist between these accountability logics, processes of negotiation are likely to be filled with complex tensions and trade-offs. Moreover, as some accountability logics are much clearer and more compelling than others, a constructivist perspective on INGO accountability does not automatically coincide with an understanding of INGO accountability in which primordial importance is given to the beneficiaries.

A fluorescence technique is used to study the mechanism and dynamics of thermoreversible gel formation in concentrated polymer solutions. Two examples of these ordered structures were studied: isotactic polystyrene (iPS) in decalin and syndiotactic poly(methyl methacrylate) (sPMMA) in toluene. iPS can form two types of gels in decalin solutions. Turbid suspensions are formed between 60°C and 130°C. When the solution is quenched beneath 20°C, transparent gels are formed. In the former solution the polymer has a 31 helix structure; in the latter a 121 helix is formed. These structures formed by iPS in decalin solution have different fluorescence spectra. The ratio (Im/Ie) of the intensity of the monomer fluorescence band in the spectrum over the intensity of the excimer emission band is higher in the spectra of transparent gels. The formation of the transparent gels from a solution can be followed by plotting Im/Ie as a function of temperature. The kinetics of the gel formation are studied by following Im/Ie as a function of time at a fixed temperature. sPMMA forms gels in toluene by a mechanism called “conformational gelation.” This mechanism consists of two steps: a fast conformational change followed by a slower aggregation of polymer chains. Both steps were followed by measuring fluorescence of a pyrene label attached to the polymer. The fluorescence lifetime of this probe is sensitive to the polarity of the environment. When the polymer conformation goes from a random coil to an all trans conformation, the environment of the fluorescent label becomes increasingly richer in solvent. This change in polarity is reflected in a change in fluorescence lifetime. The change in fluorescence anisotropy of the label reflects the second step of the mechanism and correlates with the occurrence of chain aggregation.

No abstract

No abstract

No abstract

No abstract