Qualification of piezo-electric actuators for the MADMAX booster system at cryogenic temperatures and high magnetic fields

We report on the qualification of a piezo-based linear stage for the manipulation of positions of dielectric discs in the booster of the MADMAX axion dark matter search experiment. A first demonstrator of the piezo drives, specifically developed for MADMAX, was tested at room temperature as well as at cryogenic temperatures down to 4.5 K and inside strong magnetic fields up to 5.3 T. These qualification measurements prove that the piezo-based linear stage is suited for MADMAX and fulfills the requirements.Comment: 13 pages, 9 figures, 2 table

Measuring ‘Need for Recovery’ as an indicator of staff well-being in the emergency department: a survey study

No embargo required.BackgroundThe Need for Recovery (NFR) Scale is an 11-item questionnaire that assesses how work affects intershift recovery. Items are summated to form a score with a maximum value of 100. Previously reported scores range from 38 in nurses to 55 in miners. This study aimed to determine the NFR Score among ED staff and to identify whether the NFR Score was associated with characteristics potentially implicated with recovery from work.MethodsStaff in a single ED in the South West of England (annual attendances of 93 000) were asked to complete an electronic questionnaire incorporating the NFR Scale plus additional items relating to demographic, work-related and well-being characteristics, in their own time during January 2018. Descriptive statistics are presented, including median NFR Scores and associations with additional characteristics. Thematic analysis of free-text comments from an open-ended question was undertaken.ResultsOne hundred and sixty-eight responses were obtained (80.3% capture). Median NFR Score across all staff groups was 81.8 out of 100.0 (95% CI 72.7 to 81.8). Shift duration exceeding 12 hours, dissatisfaction with work–life balance and self-reported perceptions of burnout were associated with significantly elevated NFR Scores. Themes resulting from the open-ended question were ‘barriers to intershift recovery’ and ‘coping with work’.ConclusionThe NFR Scores in this study exceeded scores reported elsewhere and were associated with some demographic, occupational and well-being characteristics. The NFR Scale has utility to measure the need for intershift recovery among ED staff. A larger study is warranted to identify specific determinants of recovery and to provide recommendations.</jats:sec

An active vesicle priming machinery suppresses axon regeneration upon adult CNS injury

Axons in the adult mammalian central nervous system fail to regenerate after spinal cord injury. Neurons lose their capacity to regenerate during development, but the intracellular processes underlying this loss are unclear. We found that critical components of the presynaptic active zone prevent axon regeneration in adult mice. Transcriptomic analysis combined with live-cell imaging revealed that adult primary sensory neurons downregulate molecular constituents of the synapse as they acquire the ability to rapidly grow their axons. Pharmacogenetic reduction of neuronal excitability stimulated axon regeneration after adult spinal cord injury. Genetic gain- and loss-of-function experiments uncovered that essential synaptic vesicle priming proteins of the presynaptic active zone, but not clostridial-toxin-sensitive VAMP-family SNARE proteins, inhibit axon regeneration. Systemic administration of Baclofen reduced voltage-dependent Ca2+ influx in primary sensory neurons and promoted their regeneration after spinal cord injury. These findings indicate that functional presynaptic active zones constitute a major barrier to axon regeneration

A new experimental approach to probe QCD axion dark matter in the mass range above 40µeV

The axion emerges in extensions of the Standard Model that explain the absence of CP violation in the strong interactions. Simultaneously, it can provide naturally the cold dark matter in our universe. Several searches for axions and axion-like particles (ALPs) have constrained the corresponding parameter space over the last decades but no unambiguous hints of their existence have been found. The axion mass range below 1 meV remains highly attractive and a well motivated region for dark matter axions. In this White Paper we present a description of a new experiment based on the concept of a dielectric haloscope for the direct search of dark matter axions in the mass range of 40 to 400 µ eV. This MAgnetized Disk and Mirror Axion eXperiment (MADMAX) will consist of several parallel dielectric disks, which are placed in a strong magnetic field and with adjustable separations. This setting is expected to allow for an observable emission of axion induced electromagnetic waves at a frequency between 10 to 100 GHz corresponding to the axion mass

Simulating MADMAX in 3D: Requirements for dielectric axion haloscopes

We present 3D calculations for dielectric haloscopes such as the currently envisioned MADMAX experiment. For ideal systems with perfectly flat, parallel and isotropic dielectric disks of finite diameter, we find that a geometrical form factor reduces the emitted power by up to 30 % compared to earlier 1D calculations. We derive the emitted beam shape, which is important for antenna design. We show that realistic dark matter axion velocities of 10-3 c and inhomogeneities of the external magnetic field at the scale of 10 % have negligible impact on the sensitivity of MADMAX. We investigate design requirements for which the emitted power changes by less than 20 % for a benchmark boost factor with a bandwidth of 50 MHz at 22 GHz, corresponding to an axion mass of 90 µ eV. We find that the maximum allowed disk tilt is 100 µ m divided by the disk diameter, the required disk planarity is 20 µ m (min-to-max) or better, and the maximum allowed surface roughness is 100 µ m (min-to-max). We show how using tiled dielectric disks glued together from multiple smaller patches can affect the beam shape and antenna coupling. © 2021 The Author(s)

A Purity Monitoring System for the H1 Liquid Argon Calorimeter

The ionization probes used for monitoring the liquid argon purity in the H1 calorimeter are described and results of their operation in tests at CERN and during the period 1992 to the end of 1998 at HERA are given. The high sensitivity of the charge measurements leads to refined charge collection models, and to the observation of a variation of the ionization yield of our electron sources with temperature.Comment: 26 pages, 14 figure

Characterization of surface defects on EXFEL series and ILC-HiGrade cavities

A detailed analysis of surface quality of around 100 EXFEL series and ILC-HiGrade SRF cavities has been performed applying high-resolution optical system OBACHT and replica. Typical surface features and defects as well as their influence on the cavity performance and possible repair methods are presented and discussed

Axon Growth of CNS Neurons in Three Dimensions Is Amoeboid and Independent of Adhesions

During development of the central nervous system (CNS), neurons polarize and rapidly extend their axons to assemble neuronal circuits. The growth cone leads the axon to its target and drives axon growth. Here, we explored the mechanisms underlying axon growth in three dimensions. Live in situ imaging and super-resolution microscopy combined with pharmacological and molecular manipulations as well as biophysical force measurements revealed that growth cones extend CNS axons independent of pulling forces on their substrates and without the need for adhesions in three-dimensional (3D) environments. In 3D, microtubules grow unrestrained from the actomyosin cytoskeleton into the growth cone leading edge to enable rapid axon extension. Axons extend and polarize even in adhesion-inert matrices. Thus, CNS neurons use amoeboid mechanisms to drive axon growth. Together with our understanding that adult CNS axons regenerate by reactivating developmental processes, our findings illuminate how cytoskeletal manipulations enable axon regeneration in the adult CNS.ISSN:2666-3864ISSN:2211-124

Fabricando monstruos o cuando el cuerpo no es suficiente De la cirugía estética a las prótesis sexuales en busca del placer / Making monsters or when the body is not enough. From cosmetic surgery to Sexual prosthesis, searching the pleasure

This article deals with concept of monstrosity and how it can be used to refer to certain sexual practices that use prostheses to increase pleasure within the BDSM -Bondage, Discipline, Sadism, Masochism- and fetishism. This reflection starts with the myths that have defined modern monsters passing to their application to certain dissenting practices which questions the patriarchal heteronormative system, after revealing how the aesthetic surgery relativizes the natural body.O presente artigo trata do conceito de monstruosidade e como ele pode ser usado para se referir a certas práticas sexuais que usam próteses para aumentar o prazer no mundo do BDSM – Bondage, Disciplina, Dominação, Submissão, Sadismo e Masoquismo – e fetichista. Fazemos uma jornada começando pelos mitos que definiram os monstros modernos, depois, passando para sua aplicação, por certas práticas dissidentes e questionadoras do sistema heteronormativo patriarcal, e então colocamos em evidência como a cirurgia estética relativiza o corpo natural.El presente artículo aborda el concepto de monstruosidad y cómo este puede emplearse para aludir a ciertas prácticas sexuales que utilizan prótesis para aumentar el placer dentro del mundo BDSM –Bondage, Disciplina, Dominación, Sumisión, Sadismo y Masoquismo– y fetichista. Se hace un recorrido comenzando por los mitos que han definido a los monstruos modernos, para luego pasar a su aplicación, a ciertas prácticas disidentes y cuestionadoras del sistema heteronormativo patriarcal, tras poner en evidencia cómo la cirugía estética relativiza el cuerpo natural

Hemorrhage in mouse tumors induced by dodecaborate cluster lipids intended for boron neutron capture therapy

Tanja Schaffran,1 Nan Jiang,1 Markus Bergmann,2,3 Ekkehard K&uuml;stermann,4 Regine S&uuml;ss,5 Rolf Schubert,5 Franz M Wagner,6 Doaa Awad,7 Detlef Gabel1,2,8 1Department of Chemistry, University of Bremen, 2Institute of Neuropathology, Klinikum Bremen-Mitte; 3Cooperative Center Medicine, University of Bremen, 4&ldquo;In-vivo-MR&rdquo; AG, FB2, University of Bremen, Bremen, 5Pharmaceutical Technology, University of Freiburg, Freiburg im Breisgau, 6Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Unversitaet Muenchen, Garching, Germany; 7Department of Biochemistry, Alexandria University, Alexandria, Egypt; 8School of Engineering and Science, Jacobs University Bremen, Bremen, Germany Abstract: The potential of boron-containing lipids with three different structures, which were intended for use in boron neutron capture therapy, was investigated. All three types of boron lipids contained the anionic dodecaborate cluster as the headgroup. Their effects on two different tumor models in mice following intravenous injection were tested; for this, liposomes with boron lipid, distearoyl phosphatidylcholine, and cholesterol as helper lipids, and containing a polyethylene glycol lipid for steric protection, were administered intravenously into tumor-bearing mice (C3H mice for SCCVII squamous cell carcinoma and BALB/c mice for CT26/WT colon carcinoma). With the exception of one lipid (B-THF-14), the lipids were well tolerated, and no other animal was lost due to systemic toxicity. The lipid which led to death was not found to be much more toxic in cell culture than the other boron lipids. All of the lipids that were well tolerated showed hemorrhage in both tumor models within a few hours after administration. The hemorrhage could be seen by in vivo magnetic resonance and histology, and was found to occur within a few hours. The degree of hemorrhage depended on the amount of boron administered and on the tumor model. The observed unwanted effect of the lipids precludes their use in boron neutron capture therapy. Keywords: liposomes, histology, magnetic resonance imaging, pharmacodynamic