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The 9th Irsee Symposium entitled “From Coadsorption and Catalysis at Solid Surfaces to Liquid–Solid Interfaces in Theory and Experiment”, sponsored by the Robert Karl Grasselli Foundation, took place at its traditional venue, the Schwäbisches Bildungszentrum in Irsee, Germany, on 16–19 June 2022. In the Irsee Symposium, selected experts gather every few years to discuss recent progress, challenges, new directions, and frontiers in catalysis. Furthermore, after the moratorium imposed on us by Covid-19, all the participants especially enjoyed the lively meeting and face-to-face interactions.

In the framework of fusion energy research based on magnetic confinement, pulsed high-field tokamaks such as Alcator and FTU have made significant scientific contributions, while several others have been designed to reach ignition, but not built yet (IGNITOR, FIRE). Equivalent stellarator concepts, however, have barely been explored. The present study aims at filling this gap by: (1) performing an initial exploration of parameters relevant to ignition and of the difficulties for a high-field stellarator approach, and, (2) proposing a preliminary high-field stellarator concept for physics studies of burning plasmas and, possibly, ignition. To minimize costs, the device is pulsed, adopts resistive coils and has no blankets. Scaling laws are used to estimate the minimum field needed for ignition, fusion power and other plasma parameters. Analytical expressions and finite-element calculations are used to estimate approximate heat loads on the divertors, coil power consumption, and mechanical stresses as functions of the plasma volume, under wide-ranging parameters. Based on these studies, and on assumptions on the enhancement-factor of the energy confinement time and the achievable plasma beta, it is estimated that a stellarator of magnetic field B  ~ 10 T and 30 m 3 plasma volume could approach or reach ignition, without encountering unsurmountable thermal or mechanical difficulties. The preliminary conceptual device is characterised by massive copper coils of variable cross-section, detachable periods, and a lithium wall and divertor.

Transposons are developing molecular tools commonly used for several applications: one of these is the delivery of genes into microorganisms. These mobile genetic elements are characterised by two repeated insertion sequences that flank a sequence encoding one or more orfs for a specific transposase that moves these sequences to other DNA sites. In the present paper, the IS2 transposon of Escherichia coli K4 was modified in vitro by replacing the sequence coding for the transposase with that of the kfoC gene that codes for chondroitin polymerase. KfoC is responsible for the polymerisation of the bacterial capsular polysaccharide whose structure is analogous to that of chondroitin sulphate, a glycosaminoglycan with established and emerging biomedical applications. The recombinant construct was stably integrated into the genome of E. coli K4 by exploiting the transposase from endogenous copies of IS2 in the E. coli chromosome. A significant improvement of the polysaccharide production was observed, resulting in 80 % higher titres in 2.5-L fed-batch cultivations and up to 3.5 g/L in 22-L fed-batch cultures.

This document is the product of a stellarator community workshop, organized by the National Stellarator Coordinating Committee and referred to as Stellcon, that was held in Cambridge, Massachusetts in February 2016, hosted by MIT. The workshop was widely advertised, and was attended by 40 scientists from 12 different institutions including national labs, universities and private industry, as well as a representative from the Department of Energy. The final section of this document describes areas of community wide consensus that were developed as a result of the discussions held at that workshop. Areas where further study would be helpful to generate a consensus path forward for the US stellarator program are also discussed. The program outlined in this document is directly responsive to many of the strategic priorities of FES as articulated in “Fusion Energy Sciences: A Ten-Year Perspective (2015–2025)” [ 1 ]. The natural disruption immunity of the stellarator directly addresses “Elimination of transient events that can be deleterious to toroidal fusion plasma confinement devices” an area of critical importance for the US fusion energy sciences enterprise over the next decade. Another critical area of research “Strengthening our partnerships with international research facilities,” is being significantly advanced on the W7-X stellarator in Germany and serves as a test-bed for development of successful international collaboration on ITER. This report also outlines how materials science as it relates to plasma and fusion sciences, another critical research area, can be carried out effectively in a stellarator. Additionally, significant advances along two of the Research Directions outlined in the report; “Burning Plasma Science: Foundations—Next-generation research capabilities”, and “Burning Plasma Science: Long pulse—Sustainment of Long-Pulse Plasma Equilibria” are proposed.

One of the most effective catalysts for the selective oxidation of propane to acrylic acid (AA) and ammoxidation to acrylonitrile (AN) is the MoV(Nb,Ta)(Te,Sb)O system, comprised of two phases, with M1 the major catalyst and M2 the co-catalyst in symbiosis with M1, converting intermediately formed propylene to the respective desired end products. An improvement in either phase should enhance the overall desired yields of a combined M1/M2 conglomerate. The current study concentrates on the M2 phase (variously substituted and/or doped) where depending on composition and preparation technique crystalline materials or crystalline materials with amorphous overlayers are obtained. Crystalline M2 catalysts without amorphous overlayers are vastly superior to those encumbered with overlayers. In a comparative study the former give a maximum AN yield of ~45% in propylene ammoxidation, the latter ~24%. In the selective oxidation of propylene to acrylic acid, the difference in performance between the two types of catalysts becomes enormous: The crystalline M2 catalyst gives a maximum AA yield of ~34% while the Te-molybdate overlayered M2 a meager ~3%. Doping of crystalline M2 phase with P significantly enhances AA yields over the base and should be seriously considered in future attempts to improve M1/M2 propane/propylene catalyst systems.

Electron Cyclotron Emission (ECE) of different frequencies originates at different locations in non-uniformly magnetized plasmas. For simultaneous observation of multiple ECE frequencies from the outside edge of a toroidal plasma confinement device (e.g. a tokamak), the focal length of the collecting optics should increase with the frequency to maximize the resolution on a line of sight along the magnetic field gradient. Here we present the design and numerical study of a zoned metamaterial lens with such characteristics, for possible deployment with the 83–130 GHz ECE radiometer in the DIII-D tokamak. The lens consists of a concentric array of miniaturized element phase-shifters. These were reverse-engineered starting from the desired Gaussian beam waist locations and further optimized to account for diffraction and finite-aperture effects that tend to displace the waist. At the same time we imposed high and uniform transmittance, averaged over all phase-shifters. The focal length is shown to increase from 1.32 m to 2.08 m over the frequency range of interest, as desired for low-field DIII-D discharges (B = −1.57 T). Retracting the lens to receded positions rigidly moves the waists accordingly, resulting in a good match—within a fraction of the Rayleigh length—of the EC-emitting layer positions at higher fields (up to B= −2.00 T). Further, it is shown how varying the lens aperture might move the waists “non-rigidly” to better match the non-rigid movement of the EC-emitting layers with the magnetic field. The numerical method presented is very general and can be used to engineer any dependence of the focal length on the frequency, including zero or minimal chromatic aberration.

The Large Magellanic Cloud, a satellite galaxy of the Milky Way, has been observed with the High Energy Stereoscopic System (H.E.S.S.) above an energy of 100 billion electron volts for a deep exposure of 210 hours. Three sources of different types were detected: the pulsar wind nebula of the most energetic pulsar known, N 157B; the radio-loud supernova remnant N 132D; and the largest nonthermal x-ray shell, the superbubble 30 Dor C. The unique object SN 1987A is, unexpectedly, not detected, which constrains the theoretical framework of particle acceleration in very young supernova remnants. These detections reveal the most energetic tip of a γ-ray source population in an external galaxy and provide via 30 Dor C the unambiguous detection of γ-ray emission from a superbubble.

Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~1015 electron volts. We report the detection of gamma rays—tracers of such cosmic rays—from the starburst galaxy NGC 253 using the High Energy Stereoscopic System (H.E.S.S.) array of imaging atmospheric Cherenkov telescopes. The gamma-ray flux above 220 billion electron volts is F = (5.5 ± 1.0stat ± 2.8sys) × 10−13 cm−2 s−1, implying a cosmic-ray density about three orders of magnitude larger than that in the center of the Milky Way. The fraction of cosmic-ray energy channeled into gamma rays in this starburst environment is five times as large as that in our Galaxy

Interleukin-1 (IL-1) is a proinflammatory cytokine that elicits its pleiotropic effects through activation of the transcription factors NF-κB and AP-1. Binding of IL-1 to its receptor results in rapid assembly of a membrane-proximal signalling complex that consists of two different receptor chains (IL-1Rs), IL-1RI and IL-1RAcP, the adaptor protein MyD88, the serine/threonine kinase IRAK and a new protein, which we have named Tollip. Here we show that, before IL-1β treatment, Tollip is present in a complex with IRAK, and that recruitment of Tollip–IRAK complexes to the activated receptor complex occurs through association of Tollip with IL-1RAcP. Co-recruited MyD88 then triggers IRAK autophosphorylation, which in turn leads to rapid dissociation of IRAK from Tollip (and IL-1Rs). As overexpression of Tollip results in impaired NF-κB activation, we conclude that Tollip is an important constituent of the IL-1R signalling pathway.