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IntroductionIn recent years, high-density microelectrode arrays (HD-MEAs) have emerged as a valuable tool in preclinical research for characterizing the electrophysiology of human induced pluripotent stem-cell-derived cardiomyocytes (iPSC-CMs). HD-MEAs enable the capturing of both extracellular and intracellular signals on a large scale, while minimizing potential damage to the cell. However, despite technological advancements of HD-MEAs, there is a lack of effective data-analysis platforms that are capable of processing and analyzing the data, particularly in the context of cardiac arrhythmias and drug testing.MethodsTo address this need, we introduce CardioMEA, a comprehensive data-analysis platform designed specifically for HD-MEA data that have been obtained from iPSCCMs. CardioMEA features scalable data processing pipelines and an interactive web-based dashboard for advanced visualization and analysis. In addition to its core functionalities, CardioMEA incorporates modules designed to discern crucial electrophysiological features between diseased and healthy iPSC-CMs. Notably, CardioMEA has the unique capability to analyze both extracellular and intracellular signals, thereby facilitating customized analyses for specific research tasks.Results and discussionWe demonstrate the practical application of CardioMEA by analyzing electrophysiological signals from iPSC-CM cultures exposed to seven antiarrhythmic drugs. CardioMEA holds great potential as an intuitive, userfriendly platform for studying cardiac diseases and assessing drug effects.

The high intensity proton accelerator complex (HIPA) at the Paul Scherrer Institute (PSI) delivers a 590 MeV CW proton beam with currents up to 2.4 mA (1.4 MW). Besides two spallation targets for thermal/cold neutrons (SINQ) and for ultracold neutrons (UCN), the beam feeds two meson production targets Target M and Target E. The targets consist of graphite wheels of effective thickness 5 mm (M) and 40/60 mm (E). The target stations M and E are of quite different design; however, both of them rotate at 1 Hz to dissipate the heat (20 kW/mA for the 40 mm target E) efficiently. Recent progress was made by a new type of bearings and a new target geometry able to increase the rate of surface muons by up to 50 %. This is also foreseen for the upgrade of the target station M within the High Intensity Muon Beam (HIMB) initiative aiming to increase the surface muons available for experiment by two orders of magnitude. HIMB is part of IMPACT (Isotope and Muon Production with Advanced Cyclotron and Target Technology), an application for the Swiss Roadmap of Research Infrastructure.

Aerolysin pores have potential to improve the accuracy of DNA sequencing and single-molecule proteomics. Here, the authors rationally design a set of mutated pores to achieve a more accurate detection of peptides and nucleic acids.

Summary: Members of the DEAD-box helicase family are involved in all fundamental processes of RNA metabolism, and as such, their malfunction is associated with various diseases. Currently, whether and how oligomerization impacts their biochemical and biological functions is not well understood. In this work, we show that DDX21, a human DEAD-box helicase with RNA G-quadruplex resolving activity, is dimeric and that its oligomerization state influences its helicase activity. Solution small-angle X-ray scattering (SAXS) analysis uncovers a flexible multi-domain protein with a central dimerization domain. While the Arg/Gly rich C termini, rather than dimerization, are key to maintaining high affinity for RNA substrates, in vitro helicase assays indicate that an intact dimer is essential for both DDX21 ATP-dependent double-stranded RNA unwinding and ATP-independent G-quadruplex remodeling activities. Our results suggest that oligomerization plays a key role in regulating RNA DEAD-box helicase activity.

Measurement of the proton beam current (0.1–40 nA) at the medical treatment facility PROSCAN at the Paul Scherrer Institut (PSI) is performed with ionization chambers. To mitigate the scattering issues and to preserve the quality of the beam delivered to the patients, a non-interceptive monitor based on the principle of a reentrant cavity resonator has been built. The resonator with a fundamental resonance frequency of 145.7 MHz was matched to the second harmonic of the pulse repetition rate (72.85 MHz) of the beam extracted from the cyclotron. This was realized with the help of ANSYS HFSS (High Frequency Structural Simulator) for network analysis. Both, the pickup position and dielectric thickness were optimized. The prototype was characterized with a stand-alone test bench. There is good agreement between the simulated and measured parameters. The observed deviation in the resonance frequency is attributed to the frequency dependent dielectric loss tangent. Hence, the dielectric had to be resized to tune the resonator to the design resonance frequency. The measured sensitivity performances were in agreement with the expectations. We conclude that the dielectric reentrant cavity resonator is a promising candidate for measuring low proton beam currents in a non-destructive manner.

Through the description of Urbain trop Urbain’s course, this article sheds light on the connection between an editorial project (to write on the contemporary city), a media (the Internet) and modes of writing. This contribution relates the writing processes of five editorial objects (a website, a Facebook wall, an Instagram account, and two digital books). It is based on notions of digital writing experimentations (author, publisher, architext, interpretation), in order to question this field on several respects: what is constitutive of meaning, work and culture, as well as the socio-technical conditions of its emergence.

Questions under study: In view of the alarming trend in childhood obesity (O) and overweight (OW) observed in certain countries, the aim of the study is to measure the prevalence of O and OW in successive cohorts of elementary school children in Geneva. Methods: All 5–6-year-old children attending public schools in the Canton of Geneva were measured and weighed during a systematic health check at school from 2003 to 2008. BMI was calculated and plotted on standardised BMI for age tables, using Cole’s and Kromeyer’s references. Results: Using Cole’s references, the overall trend was a small non-significant decrease for OW 0.7 points (p = 0.33) and O 0.5 points (p = 0.23) over the 5-year period. For girls, OW decreased by 1.1 point (p = 0.47) and O decreased by 0.5 points (p = 0.61), whilst for boys OW decreased by 0.3 points (p = 0.54) and O decreased by 0.6 points (p = 0.23). A non-significant decrease or stabilisation in the prevalence of overweight and obesity was observed over the 5-year period in both boys and girls. Conclusion: These observations corroborate observations from Sweden and France, showing a levelling off in obesity and overweight in young children.

• Reentrant cavity resonator as a beam current monitor for proton medical cyclotrons. • The monitor can measure as low as sub-nano ampere with 50pA resolution. • The monitor helps to preserve the beam quality as it is non-interceptive. At PSI (Paul Scherrer Institute), Switzerland, a superconducting cyclotron called "COMET" delivers proton beam of 250 MeV pulsed at 72.85 MHz for proton radiation therapy. Measuring proton beam currents (0.1–10nA) is of crucial importance for the treatment safety and is usually performed with invasive monitors such as ionisation chambers (ICs) which degrade the beam quality. A new non-invasive beam current monitor working on the principle of electromagnetic resonance is built to replace ICs in order to preserve the beam quality delivered. The fundamental resonance frequency of the resonator is tuned to 145.7 MHz, which is the second harmonic of the pulse rate, so it provides signals proportional to beam current. The cavity resonator installed in the beamline of the COMET is designed to measure beam currents for the energy range 238–70 MeV. Good agreement is reached between expected and measured resonator response over the energy range of interest. The resonator can deliver beam current information down to 0.15 nA for a measurement integration time of 1 s. The cavity resonator might be applied serving as a safety monitor to trigger interlocks within the existing domain of proton radiation therapy. Low beam currents limit the abilities to detect sufficiently, however, with the potential implementation of FLASH proton therapy, the application of cavity resonator as an online beam-monitoring device is feasible. [ABSTRACT FROM AUTHOR]

This paper addresses the collaboration between photographer Richard Misrach and landscape architect Kate Orff, which gave way to various creative exhibitions as well as the book, Petrochemical America (2012). The originality of this work can be found in the mobilization of landscape design tools to produce, from the seminal “scene” of photography, a kind of reverse engineering of the industrial landscape factory. In turn, the photographic representation effects – its “punctum” – is amplified through a singular genealogy of the altered landscape.