Building connectomes using diffusion MRI: why, how and but

Why has diffusion MRI become a principal modality for mapping connectomes in vivo? How do different image acquisition parameters, fiber tracking algorithms and other methodological choices affect connectome estimation? What are the main factors that dictate the success and failure of connectome reconstruction? These are some of the key questions that we aim to address in this review. We provide an overview of the key methods that can be used to estimate the nodes and edges of macroscale connectomes, and we discuss open problems and inherent limitations. We argue that diffusion MRI-based connectome mapping methods are still in their infancy and caution against blind application of deep white matter tractography due to the challenges inherent to connectome reconstruction. We review a number of studies that provide evidence of useful microstructural and network properties that can be extracted in various independent and biologically-relevant contexts. Finally, we highlight some of the key deficiencies of current macroscale connectome mapping methodologies and motivate future developments

Control of the Crystallization and Phase Separation Kinetics in Sequential Blade‐Coated Organic Solar Cells by Optimizing the Upper Layer Processing Solvent

Sequential deposition of the active layer in organic solar cells (OSCs) is favorable to circumvent the existing drawbacks associated with controlling the microstructure in bulk-heterojunction (BHJ) device fabrication. However, how the processing solvents impact on the morphology during sequential deposition processes is still poorly understood. Herein, high-efficiency OSCs are fabricated by a sequential blade coating (SBC) through optimization of the morphology evolution process induced by processing solvents. It is demonstrated that the device performance is highly dependent on the processing solvent of the upper layer. In situ morphology characterizations reveal that an obvious liquid–solid phase separation can be identified during the chlorobenzene processing of the D18 layer, corresponding to larger phase separation. During chloroform (CF) processing of the D18 layer, a proper aggregation rate of Y6 and favorable intermixing of lower and upper layers results in the enhanced crystallinity of the acceptor. This facilitates efficient exciton dissociation and charge transport with an inhibited charge recombination in the D18/CF-based devices, contributing to a superior performance of 17.23%. These results highlight the importance of the processing solvent for the upper layer in the SBC strategy and suggest the great potential of achieving optimized morphology and high-efficiency OSCs using the SBC strategy

The politics of liberal internationalism

How is it that internationalism has become the dominant form of statecraft pursued by liberal states and by international organisations, and yet it has received relatively scant attention in International Relations (IR) both historically and conceptually? It is time that the field addressed the paucity of writings on an institutionalised idea that has shaped order-building for more than two centuries. The article opens with a consideration of internationalism and its status in political theory and IR, arguing that a variety of different configurations have taken hold in different historical moments. We then consider the coexistence of internationalism and imperialism as an illustration of how the ambiguities and tensions in liberal statecraft can be manifested. The article closes with a consideration of the international normative order-building that has taken place after 1945 and the critical issue of the resilience of liberal internationalism given the 'crisis' identified with it. For all its dangers and dilemmas, we make the case for engaging the politics of liberal internationalism as a site in which normative and practical concerns of global politics meet, and in which the calls to protect the interests of national communities are mediated by the imperative of 'purposes beyond ourselves'