École Polytechnique Fédérale de Lausanne
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Soft Printable Electrode Coating for Neural Interfaces
No full textThe mechanical mismatch between implantable interfaces and neural tissues may be reduced by employing soft polymeric materials. Here, we report on a simple strategy to prepare and pattern a soft electrode coating of neural interfacing devices based on a screen-printable conducting hydrogel. The coating formulation, based on polyacrylamide and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, is suitable to additive manufacturing and exhibits excellent adhesion to polydimethylsiloxane, an elastomer commonly used as a substrate in soft neural interfaces. The soft conductive coating displays a tunable elastic modulus in the 10–100 kPa range and electrochemical properties on a par with stiff conductive inks while supporting good neural cell attachment and proliferation in vitro. Next, the soft printable hydrogel is integrated within a 4 × 4 microelectrode array for electrocorticography with 250 μm-diameter contacts. Acute recording of cortical local field potentials and electrochemical characterization preimplantation and postimplantation highlight the stability of the soft organic conductor. The overall robustness of the soft coating and its patterning method provide a promising route for a range of implantable bioelectronic applications.LSBIUPCOURTIN
The Advent of the 4D Mirror World
No full textThe 4D Mirror World is considered to be the next planetary-scale information platform. This commentary gives an overview of the history of the converging trends that have progressively shaped this concept. It retraces how large-scale photographic surveys served to build the first 3D models of buildings, cities, and territories, how these models got shaped into physical and virtual globes, and how eventually the temporal dimension was introduced as an additional way for navigating not only through space but also through time. The underlying assumption of the early large-scale photographic campaign was that image archives had deeper depths of latent knowledge still to be mined. The technology that currently permits the advent of the 4D World through new articulations of dense photographic material combining aerial imagery, historic photo archives, huge video libraries, and crowd-sourced photo documentation precisely exploits this latent potential. Through the automatic recognition of “homologous points,” the photographic material gets connected in time and space, enabling the geometrical computation of hypothetical reconstructions accounting for a perpetually evolving reality. The 4D world emerges as a series of sparse spatiotemporal zones that are progressively connected, forming a denser fabric of representations. On this 4D skeleton, information of cadastral maps, BIM data, or any other specific layers of a geographical information system can be easily articulated. Most of our future planning activities will use it as a way not only to have smooth access to the past but also to plan collectively shared scenarios for the future.DHLABIAGS-GEThis is an open access article distributed under the terms of the Creative Commons Attribution 4.0 license (http://creativecommons.org/licenses/by/4.0), which permits any use, distribution, and reproduction of the work without further permission provided the original author(s) and source are credited
Prolongement du Pont sur le Rhône à Aproz
No full textL'objectif du projet est l’analyse du pont existant en termes de durabilité et de sécurité structurelle et, si nécessaire, de proposer un renforcement pour compenser les défauts. En outre, dans le cadre de la correction du Rhône, qui, à proximité de la commune d'Aproz, implique une extension du pont d'environ 34.6 m. Deux variantes ont été dimensionnées, une en béton armé et une en BFUP armé, dans le but de trouver la solution optimale en termes de sécurité structurelle, de durabilité et de délais de construction.SGCMC
Thermally regenerative copper nanoslurry flow batteries for heat-to-power conversion with low-grade thermal energy
No full textLow-grade heat (below 200 °C) is available in vast quantities from industry, or from standard roof-top solar thermal collectors. However, the production of electric power from these heat sources is challenging with existing technologies. Thermally regenerative batteries allow both the conversion and the storage of thermal energy into electric power, but they suffer from low operation voltages and low output power. Here, we propose a thermally regenerative nanoslurry flow battery based on copper complexation with acetonitrile in non-aqueous solutions operating at voltages above 1 V. The Cu(I) complex can be destabilized by the removal of acetonitrile by distillation, leading to the production of solid copper nanoparticles and Cu(II) in solution, thereby charging the battery. We demonstrate the electricity production at average power densities of 90 W m−2 and peak-power densities up to 150 W m−2, and estimate the theoretical efficiency of the full system at 2%. The results demonstrate a proof-of-concept for harvesting and storage of electricity from low-quality heat.LEPAThis article is licensed under a Creative Commons Attribution 3.0 Unported Licence
The Social Life of Heritage-Making: Cultural Representations and Frictions
No full textThe chapter explores the social and historic construction of heritage and the role played in this by institutions, from an anthropological perspective. Since state members ratified the UNESCO Conventions, national inventories have been collated so that candidacies can be submitted to international lists and, in turn, the benefits of this cultural showcase return to the nation. Based on ethnographic fieldwork in China and Switzerland, this chapter focuses on the logic underlying processes of selection, which involves both political and administrative bodies. The evaluation of how cultural heritage acts, and is interpreted by various stakeholders will be outlined along with an analysis of which practices and narratives almost inevitably produce friction. The case studies presented highlight the complexity of cultural meanings and frictions among multi-layered stakeholders who claim their ‘rights to cultural heritage’ and, in doing so, challenge the norms and values that it carries which, they feel, must be transmitted to the next generation.IAGS-GESCI-ENAC-FGBgrpc
Global uncertainty-sensitivity analysis on mechanistic kinetic models: From model assessment to theory-driven design of nanoparticles
No full textRecently, we developed a population balance framework describing the precipitation of calcium-silicate-hydrate, a key nanomaterial in the construction industry and with potential applications in biomedicine, environmental remediation, and catalysis. In this article, we first refine our computational workflow by developing a more efficient and robust method for the solution of the moment-transformed population balance equations. Then, we generalize our framework by coupling to PHREEQC, a widely used opensource speciation solver, to enhance the adaptability of the framework to new systems. Using this improved computational model, we perform global uncertainty/sensitivity analysis (UA/SA) to understand the effect of variations in the model parameters and experimental conditions on the properties of the product. With the specific surface area of particles as an example, we show that UA/SA identifies the factors whose control would allow a fine-tuning of the desired properties. This general approach can be transferred to other nanoparticle synthesis schemes as well. (C) 2020 The Authors. Published by Elsevier Ltd.GR-LUDLMCThis is an open access article under the CC BY license
Divide-and-Rule: Self- Supervised Learning for Survival Analysis in Colorectal Cancer
No full textLTS
Gas-sieving zeolitic membranes fabricated by condensation of precursor nanosheets
No full textThe synthesis of molecular-sieving zeolitic membranes by the assembly of building blocks, avoiding the hydrothermal treatment, is highly desired to improve reproducibility and scalability. Here we report exfoliation of the sodalite precursor RUB-15 into crystalline 0.8-nm-thick nanosheets, that host hydrogen-sieving six-membered rings (6-MRs) of SiO(4)tetrahedra. Thin films, fabricated by the filtration of a suspension of exfoliated nanosheets, possess two transport pathways: 6-MR apertures and intersheet gaps. The latter were found to dominate the gas transport and yielded a molecular cutoff of 3.6 angstrom with a H-2/N(2)selectivity above 20. The gaps were successfully removed by the condensation of the terminal silanol groups of RUB-15 to yield H-2/CO(2)selectivities up to 100. The high selectivity was exclusively from the transport across 6-MR, which was confirmed by a good agreement between the experimentally determined apparent activation energy of H(2)and that computed by ab initio calculations. The scalable fabrication and the attractive sieving performance at 250-300 degrees C make these membranes promising for precombustion carbon capture. Zeolite membranes can be used for gas molecular sieving, but synthesis requires complex hydrothermal treatment. Here, single layers of zeolite precursor RUB-15 are exfoliated followed by a condensation reaction, forming zeolite membranes with H-2/CO(2)selectivity of 20 to 100 in a facile process.COSMOLASISIC-G
How specific are the conformation-specific α-synuclein antibodies? Characterization and validation of 16 α-synuclein conformation-specific antibodies using well-characterized preparations of α-synuclein monomers, fibrils and oligomers with distinct structures and morphology
No full textIncreasing evidence suggests that alpha-synuclein (α-syn) oligomers are obligate intermediates in the pathway involved in α-syn fibrillization and Lewy body (LB) formation, and may also accumulate within LBs in Parkinson's disease (PD) and other synucleinopathies. Therefore, the development of tools and methods to detect and quantify α-syn oligomers has become increasingly crucial for mechanistic studies to understand their role in PD, and to develop new diagnostic methods and therapies for PD and other synucleinopathies. The majority of these tools and methods rely primarily on the use of aggregation state-specific or conformation-specific antibodies. Given the impact of the data and knowledge generated using these antibodies on shaping the foundation and directions of α-syn and PD research, it is crucial that these antibodies are thoroughly characterized, and their specificity or ability to capture diverse α-syn species is tested and validated. Herein, we describe an antibody characterization and validation pipeline that allows a systematic investigation of the specificity of α-syn antibodies using well-defined and well-characterized preparations of various α-syn species, including monomers, fibrils, and different oligomer preparations that are characterized by distinct morphological, chemical and secondary structure properties. This pipeline was used to characterize 18 α-syn antibodies, 16 of which have been reported as conformation- or oligomer-specific antibodies, using an array of techniques, including immunoblot analysis (slot blot and Western blot), a digital ELISA assay using single molecule array technology and surface plasmon resonance. Our results show that i) none of the antibodies tested are specific for one particular type of α-syn species, including monomers, oligomers or fibrils; ii) all antibodies that were reported to be oligomer-specific also recognized fibrillar α-syn; and iii) a few antibodies showed high specificity for oligomers and fibrils but did not bind to monomers. These findings suggest that the great majority of α-syn aggregate-specific antibodies do not differentiate between oligomers and fibrils, thus highlighting the importance of exercising caution when interpreting results obtained using these antibodies. Our results also underscore the critical importance of the characterization and validation of antibodies before their use in mechanistic studies and as diagnostic tools or therapeutic agents. This will not only improve the quality and reproducibility of research and reduce costs but will also reduce the number of therapeutic antibody failures in the clinic.LMNNThis article is licensed under a Creative Commons Attribution 4.0 International Licens
The Identity of Entrepreneurs: Providing Conceptual Clarity and Future Directions
No full textTheidentity of entrepreneurs(IoE) has become a popular concept in entrepreneurship research, for example, to explain entrepreneurial behavior. Yet, despite growing interest in this topic, theoretical and terminological inconsistencies have hampered the development of a coherent understanding of the identity of entrepreneurs. I conduct a systematic literature review to provide an overview of different theoretical perspectives in IoE research and suggest consistent use of terminology and operationalizations. Further, I propose a framework to investigate the dynamic nature and multi-level influences of the identity of entrepreneurs, and outline meaningful avenues for future research to unravel when, how, and with what consequences identity may become relevant in new venture creation.SHS-EN