Interplay of coarsening, aging, and stress hardening impacting the creep behavior of a colloidal gel

We explore the dynamical and mechanical characteristics of an evolving gel in diffusing wave spectroscopy (DWS) and rheometry, aiming to assess how the gel evolution impacts the creep response of the system. Our gel is formed by inducing the aggregation of thermosensitive colloids by a variation in temperature. We find experimental evidence that the long time evolution of this gel is due to two distinct processes: A coarsening process that involves the incorporation of mobile particles into the network structure and an aging process that triggers intermittent rearrangement events. While coarsening is the main process governing the evolution of the elastic properties of the gel, aging is the process determining structural relaxation. The combination of both processes in addition to stress hardening governs the creep behavior of the gel, a creep behavior that is determined by three distinct contributions: an instantaneous elastic, a delayed elastic, and a loss contribution. The systematic investigation of these contributions in recovery experiments provides evidence that losses and delayed elastic storage have a common origin, both being due to intermittent local structural relaxation events

Point-Contact Spectroscopy in MgB_2: from Fundamental Physics to Thin-Film Characterization

In this paper we highlight the advantages of using point-contact spectroscopy (PCS) in multigap superconductors like MgB_2, both as a fundamental research tool and as a non-destructive diagnostic technique for the optimization of thin-film characteristics. We first present some results of crucial fundamental interest obtained by directional PCS in MgB_2 single crystals, for example the temperature dependence of the gaps and of the critical fields and the effect of a magnetic field on the gap amplitudes. Then, we show how PCS can provide useful information about the surface properties of MgB_2 thin films (e.g. Tc, gap amplitude(s), clean or dirty-limit conditions) in view of their optimization for the fabrication of tunnel and Josephson junctions for applications in superconducting electronics.Comment: 11 pages, 7 figures; Proceedings of 6th EUCAS Conference (14-18 September 2003, Sorrento - Italy

A REPLICABLE OPEN-SOURCE MULTI-CAMERA SYSTEM FOR LOW-COST 4D GLACIER MONITORING

Image-based monitoring has emerged as a prevalent technique for sensing mountain environments. Monoscopic time-lapse cameras, which rely on digital image correlation to quantify glacier motion, have limitations due to the need for a Digital Elevation Model for deriving 3D flow velocity fields. Multi-camera systems overcome this limitation, as they allow for a 3D reconstruction of the scene. This paper presents a replicable low-cost stereoscopic system designed for 4D glacier monitoring. The system consists of independent and autonomous units, built from off-the-shelves components, such as a DSLR camera, an Arduino microcontroller, and a Raspberry Pi Zero, reducing costs compared to pre-built time-lapse cameras. The units are energetically self-sufficient and resistant to harsh alpine conditions. The system was successfully tested for more than a year to monitor the northwest terminus of the Belvedere Glacier (Italian Alps). Daily stereo-pairs acquired were processed with Structure-from-Motion to derive 3D point clouds of the glacier terminus and estimate glacier retreat and ice volume loss. By combining the information about ice volume loss with ablation estimates and ice flow velocity information, e.g., derived from monoscopic-camera time series, a multi-camera system enables a comprehensive understanding of sub-seasonal glacier dynamics

Search algorithms as a framework for the optimization of drug combinations

Combination therapies are often needed for effective clinical outcomes in the management of complex diseases, but presently they are generally based on empirical clinical experience. Here we suggest a novel application of search algorithms, originally developed for digital communication, modified to optimize combinations of therapeutic interventions. In biological experiments measuring the restoration of the decline with age in heart function and exercise capacity in Drosophila melanogaster, we found that search algorithms correctly identified optimal combinations of four drugs with only one third of the tests performed in a fully factorial search. In experiments identifying combinations of three doses of up to six drugs for selective killing of human cancer cells, search algorithms resulted in a highly significant enrichment of selective combinations compared with random searches. In simulations using a network model of cell death, we found that the search algorithms identified the optimal combinations of 6-9 interventions in 80-90% of tests, compared with 15-30% for an equivalent random search. These findings suggest that modified search algorithms from information theory have the potential to enhance the discovery of novel therapeutic drug combinations. This report also helps to frame a biomedical problem that will benefit from an interdisciplinary effort and suggests a general strategy for its solution.Comment: 36 pages, 10 figures, revised versio

On reminder effects, drop-outs and dominance: evidence from an online experiment on charitable giving

We present the results of an experiment that (a) shows the usefulness of screening out drop-outs and (b) tests whether different methods of payment and reminder intervals affect charitable giving. Following a lab session, participants could make online donations to charity for a total duration of three months. Our procedure justifying the exclusion of drop-outs consists in requiring participants to collect payments in person flexibly and as known in advance and as highlighted to them later. Our interpretation is that participants who failed to collect their positive payments under these circumstances are likely not to satisfy dominance. If we restrict the sample to subjects who did not drop out, but not otherwise, reminders significantly increase the overall amount of charitable giving. We also find that weekly reminders are no more effective than monthly reminders in increasing charitable giving, and that, in our three months duration experiment, standing orders do not increase giving relative to one-off donations

Ab-initio study of model guanine assemblies: The role of pi-pi coupling and band transport

Several assemblies of guanine molecules are investigated by means of first-principle calculations. Such structures include stacked and hydrogen-bonded dimers, as well as vertical columns and planar ribbons, respectively, obtained by periodically replicating the dimers. Our results are in good agreement with experimental data for isolated molecules, isolated dimers, and periodic ribbons. For stacked dimers and columns, the stability is affected by the relative charge distribution of the pi orbitals in adjacent guanine molecules. pi-pi coupling in some stacked columns induces dispersive energy bands, while no dispersion is identified in the planar ribbons along the connections of hydrogen bonds. The implications for different materials comprised of guanine aggregates are discussed. The bandstructure of dispersive configurations may justify a contribution of band transport (Bloch type) in the conduction mechanism of deoxyguanosine fibres, while in DNA-like configurations band transport should be negligible.Comment: 21 pages, 6 figures, 3 tables, to be published in Phys. Rev.

Efficacy of Benralizumab in severe asthma in real life and focus on nasal polyposis

Introduction: Severe asthma occurs in 5–10% of asthmatic patients, with nasal polyposis as one of the most frequent comorbidity. Benralizumab was recently marketed, thus we could analyse its effects in real-life in severe asthma, and compare the effects of the drug in patients with and without polyposis. Methods: Patients with severe asthma, receiving Benralizumab were enrolled in Italian asthma centres. The efficacy criteria for asthma (exacerbation rate, oral corticosteroid intake, hospitalizations, pulmonary function, exhaled nitric oxide) were evaluated at baseline and after 24 weeks of treatment. Patients were then sub-analysed according to the presence/absence of nasal polyposis. Results: Fifty-nine patients with severe uncontrolled asthma (21 males, age range 32–78) and treated with benralizumab for at least 24 weeks has been evaluated, showing significant improvements in asthma-related outcomes, except for pulmonary function and exhaled nitric oxide. This included a reduction in the sino-nasal outcome-22 score versus baseline of 13.7 points (p = .0037) in the 34 patients with nasal polyposis. Anosmia disappeared in 31% patients (p = .0034). When comparing the groups with and without nasal polyposis, a similar reduction of exacerbations was seen, with a greater reduction of the steroid dependence in patients with polyposis (−72% vs −53%; p < .0001), whereas lung function was significantly more improved (12% vs 34%, p = .0064) without polyposis patients. Conclusions: Benralizumab, after 6 months of treatment, confirmed its efficacy in severe asthma, and also in nasal polyposis, which is the most frequent comorbidity. The efficacy of Benralizumab in reducing steroid dependence was even higher in patients with polyposis

Retail ring-fencing of banks and its implications

Financial stability remains a key theme globally in view of the Euro zone debt crisis. The latest strategy by Germany and France is to ring-fence the crisis among the PIIGS countries (Portugal, Greece, Ireland, Italy and Spain). In the United Kingdom, the big four major banks have all responded to the Independent Commission of Bankings interim report key recommendation: ring-fencing retail operations into a separate subsidiary of any bank that wishes to operate in the United Kingdom. The report has clearly discussed the advantages and disadvantages of various types of subsidiarisation. Retail ring-fencing is considered a compromise as full subsidiarisation is too costly and operational subsidiarisation is too minimal. The Independent Commission of Banking published its final report on 12 September 2011. They recommended ring-fencing retail banking and a 10 per cent equity baseline. This article focuses on structural reforms of UK banks. It aims to address the question of financial stability from a wider European perspective. The first question is whether cross-border retail banking in the European Economic Area (EEA) is best served by branches or subsidiaries? The second question concerns the legality of setting up subsidiaries in the European Union (EU). Although there are no legal problems for UK-based banks setting up subsidiaries for their retail activities, there might be a legal hurdle for requiring foreign banks setting up subsidiaries in the United Kingdom. The third question concerns EU cross-border banking regulation and supervision. Are the passporting system and the home country supervisory approach still applicable in this post-financial crisis era? Many factors influence the choice of setting up branches or subsidiaries. However, the general position is that branches are more suited for wholesale/investment activities because of ease of funds transfer. Subsidiaries are more suitable for retail banking because of the limited liability principle and extensive local network. Effective cross-border banking must be accompanied by effective supervision and resolution regimes. The passporting concept under EU law and home country dominance are somewhat dated post-financial crisis. Host country control should play a dominant part in financial regulation, especially in the light of the importance of subsidiaries and the limited liability principle associated with them. The Icelandic bank crisis and collapse of Lehman Brothers International Europe illustrate the importance of host country control. Finally, the author argues that requiring banks to hold its retail activities in the form of subsidiaries in another European country is necessary to achieve financial stability. © 2012 Macmillan Publishers Ltd