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A reversed-field pinch is a toroidal device for magnetically confining plasmas, and a potential alternative to the tokamak for a future fusion reactor. Observations of the evolution of a reversed-field-pinch plasma towards a self-organized single-helicity state suggest that instability problems, which have previously hindered the development of these devices, could now be overcome. In the quest for new energy sources, the research on controlled thermonuclear fusion 1 has been boosted by the start of the construction phase of the International Thermonuclear Experimental Reactor 2 (ITER). ITER is based on the tokamak magnetic configuration 3 , which is the best performing one in terms of energy confinement. Alternative concepts are however actively researched, which in the long term could be considered for a second generation of reactors. Here, we show results concerning one of these configurations, the reversed-field pinch 4 , 5 (RFP). By increasing the plasma current, a spontaneous transition to a helical equilibrium occurs, with a change of magnetic topology. Partially conserved magnetic flux surfaces emerge within residual magnetic chaos, resulting in the onset of a transport barrier. This is a structural change and sheds new light on the potential of the RFP as the basis for a low-magnetic-field ohmic fusion reactor.

The experimental fusion reactor ITER will feature two (or three) heating neutral beam injectors (NBI) capable of delivering 33(or 50) MW of power into the plasma. A NBI consists of a plasma source for production of negative ions (extracted negative ion current up to 329 A/m 2 in H and 285 A/m 2 in D) then accelerated up to 1 MeV for one hour. The negative ion beam is neutralized, and the residual ions are electrostatically removed before injection. The beamline was designed for a beam divergence between 3 and 7 mrad. The ion source in ITER NBIs relies on RF-driven, Inductively-Coupled Plasmas (ICP), based on the prototypes developed at IPP Garching; RF-driven negative-ion beam sources have never been employed in fusion devices up to now. The recent results of SPIDER, the full size ITER NBI ion source operating at NBTF in Consorzio RFX, Padova, measure a beamlet divergence minimum of 12mrad and highlighted beam spatial non-uniformity. SPIDER results confirmed the experimental divergence found in smaller prototype sources, which is larger compared to filament-arc ion sources. Although prototype experiments have shown that the extracted current requirement can be achieved with minor design improvements, the beamlet divergence is expected to marginally achieve the design value of 7 mrad, which in multi-grid long accelerators results in unexpected heat loads over the accelerator grids. A contributor to the beam divergence is the energy/temperature of the extracted negative ions, so it is believed that plasma differences between the two source types play a role. Research is focused on the plasma parameters in the ion source. One RF driver, identical to the ones used in SPIDER, installed in a relatively small-scale experimental set-up, inherently more flexible than large devices, is starting operations devoted to the investigation of the properties of RF-generated plasmas, so as to contribute to the assessment of negative ion precursors, and of their relationship with the plasma parameters, particularly when enhancing plasma confinement. The scientific questions, that have arisen from the preliminary results of SPIDER, guided the design of the test stand, which are described in this contribution, together with the diagnostic systems and related simulation tools. The test stand, which shares with the larger experiment all the geometrical features and constraints, will allow technological developments and optimized engineering solutions related to the ICP design for the ITER NBIs.

The Neutral Beam Injectors of the ITER experiment will rely on negative ion sources to produce 16.7 MW beams of H/D particles accelerated at 1 MeV. The prototype of these sources was built and is currently operated in the SPIDER experiment (Source for the Production of Ions o Deuterium Extracted from an RF plasma), part of the Neutral Beam Test Facility of Consorzio RFX, Padua. In SPIDER, the H-/D- ion source is coupled to a three grids 100 kV acceleration system. One of the main targets of the experimentation in SPIDER is to uniformly maximize the extracted current density; to achieve this it is important to study the density of negative ions available in proximity of the ion acceleration system. In SPIDER, line-integrated measurements of negative ion density are performed by a Cavity Ring Down Spectroscopy (CRDS) diagnostic. Its principle of operation is based on the absorption of the photons of a laser beam pulse by H-/D- photo-detachment; the absorption detection is enhanced by trapping the laser pulse in an optical cavity, containing the absorbing medium (i.e. negative ions). The paper presents and discusses the CRDS diagnostic setup in SPIDER, including the first measurements of negative ion density, correlated to the main source parameters.

Recent advances in acquisition equipment is providing experiments with growing amounts of precise yet affordable sensors. At the same time an improved computational power, coming from new hardware resources (GPU, FPGA, ACAP), has been made available at relatively low costs. This led us to explore the possibility of completely renewing the chain of acquisition for a fusion experiment, where many high-rate sources of data, coming from different diagnostics, can be combined in a wide framework of algorithms. If on one hand adding new data sources with different diagnostics enriches our knowledge about physical aspects, on the other hand the dimensions of the overall model grow, making relations among variables more and more opaque. A new approach for the integration of such heterogeneous diagnostics, based on composition of deep variational autoencoders, could ease this problem, acting as a structural sparse regularizer. This has been applied to RFX-mod experiment data, integrating the soft X-ray linear images of plasma temperature with the magnetic state. However to ensure a real-time signal analysis, those algorithmic techniques must be adapted to run in well suited hardware. In particular it is shown that, attempting a quantization of neurons transfer functions, such models can be modified to create an embedded firmware. This firmware, approximating the deep inference model to a set of simple operations, fits well with the simple logic units that are largely abundant in FPGAs. This is the key factor that permits the use of affordable hardware with complex deep neural topology and operates them in real-time.

The potential for global warming and climate change has increased the focus of research on plant genes that respond to high temperatures. Previous research identified a temperature-sensitive miniature soybean mutant that was controlled by a single gene. The objectives of our research were to confirm the single-gene control and to determine the genomic location of this gene. Segregation of the combined progeny of four BC∧6F∧5 plants heterozygous for the miniature trait in a Tracy-M background confirmed that the trait was conditioned by a single gene (1:2:1, χ²=4.38, P=0.1120). Molecular marker analysis identified three SSR markers and a SNP marker on molecular linkage group B2 (chromosome 14) associated with segregation for the miniature trait. One of these, marker Satt560, co-segregated perfectly with the miniature trait. The data from these four polymorphic markers indicated that the gene conditioning this miniature phenotype is at or near Satt560. Given this newly identified location of the gene and the recently published soybean genomic sequence, it may be feasible to isolate the gene and determine its mechanism of action in responding to temperature. Such knowledge may be of use in understanding how plants respond to increased temperature.

To the Editor: The recent investigation by Cohn et al. (June 12 issue) 1 offers hope that therapy with isosorbide dinitrate and hydralazine may improve survival in patients with chronic congestive heart failure. In this randomized study, the three treatment groups (placebo, prazosin, or hydralazine–nitrate) were nearly identical with respect to the base-line clinical characteristics presented in the report. However, data describing the presence and degree of baseline ventricular arrhythmias in the three groups were not included. The independent association of serious ventricular arrhythmias with survival in patients with chronic congestive heart failure has not been firmly established. 2 However, the presence . . . No extract is available for articles shorter than 400 words.

Patient-reported outcome measures (PROMs) capture disease severity metrics from the patient’s perspective, including health-related quality of life (HRQL). Disease-specific validation of PROMs improves their clinical utility. We evaluated construct validity (HRQL) for Skindex-16 in routinely seen psoriasis patients and characterized instances of discordance between Skindex-16 scores and clinician-reported outcome measure of disease severity. We retrospectively studied psoriasis patients seen by University of Utah Dermatology from 2016 to 2020. Cross-sectional construct validity was assessed using quantile regression and Spearman correlation between overall physician global assessment (OPGA) score and Skindex-16 scores. Longitudinal within-subject correlation was performed using linear mixed models. Discordance (10th percentile or lower OPGA and 90th percentile or higher Skindex-16 score [clear skin, poor HRQL; cspHRQL] or the reverse [severe skin, good HRQL; ssgHRQL]) was characterized descriptively. 681 first-visit patients with psoriasis were included. Median overall Skindex-16 score varied by ≥ 10 points across all levels of OPGA scores. OPGA and Skindex-16 domain scores were moderately correlated (emotions ρ = 0.54, functioning ρ = 0.47, and symptoms ρ = 53). Longitudinal correlations were similar (emotion ρ xy  = 0.54, functioning ρ xy  = 0.65, symptoms ρ xy  = 0.47). Visits with cspHRQL discordance occurred for each Skindex-16 domain (emotions = 7, functioning = 13, symptoms = 12). The ssgHRQL group was observed within the emotions ( n  = 1) and functioning ( n  = 23) domains. Median Skindex-16 scores are different between different levels of OPGA and show moderate cross-sectional and longitudinal correlation. This supports construct validity in patients with psoriasis. Severe discordance was rare and most often for those with clear skin but poor HRQL. These discordances can prompt further patient–clinician conversation.

A measurement of the jet mass distribution in hadronic decays of Lorentz-boosted top quarks is presented. The measurement is performed in the lepton + jets channel of top quark pair production ( ) events, where the lepton is an electron or muon. The products of the hadronic top quark decay are reconstructed using a single large-radius jet with transverse momentum greater than 400 . The data were collected with the CMS detector at the LHC in proton-proton collisions and correspond to an integrated luminosity of 138 . The differential production cross section as a function of the jet mass is unfolded to the particle level and is used to extract the top quark mass. The jet mass scale is calibrated using the hadronic W boson decay within the large-radius jet. The uncertainties in the modelling of the final state radiation are reduced by studying angular correlations in the jet substructure. These developments lead to a significant increase in precision, and a top quark mass of .

Alopecia areata (AA) is a common autoimmune disease that results in non-scarring hair loss. AA pathogenesis is thought to involve multiple inflammatory cytokines. Apremilast is a phosphodiesterase 4 (PDE4) inhibitor that reduces pro-inflammatory cytokine production. Recent studies demonstrate upregulation of PDE4 in human scalp lesions of AA patients and hair regrowth in a humanized AA mouse model upon apremilast treatment, suggesting a possible potential of apremilast in AA. To assess the efficacy and safety of apremilast in AA, we conducted a double-blind, placebo-controlled single-center pilot study in 30 moderate-to-severe AA patients (≥ 50% scalp involvement) that were randomized 2:1 to receive apremilast (n = 20) or placebo (n = 10) orally for 24 weeks. The primary endpoint was the percentage of patients achieving 50% reduction in severity of alopecia tool (SALT) score (SALT50) at 24 weeks compared to baseline, and the secondary endpoints included the percent change in SALT score at weeks 24 and 48. Eight patients in the apremilast arm withdrew prior to week 24 along with two patients in the placebo group, mostly due to lack of efficacy and adverse events. At 24 weeks, only 1 of 12 apremilast-treated subjects achieved SALT50, and similarly 1 of 8 placebo-treated subjects achieved SALT50. The difference between the mean percent improvement in SALT score at week 24 compared to baseline of the two study arms was not statistically significant (p = 0.38). The lack of treatment response in most of our patients argues against a pathogenic role for PDE4 specifically in moderate-to-severe AA, but targeting this pathway may still be of value in patients with mild AA as there is less of an inflammatory burden in this population. However, future larger studies may be needed to conclude apremilast’s lack of efficacy in moderate-to-severe AA.

Exome and genome sequencing have greatly improved the diagnosis of rare genetic disorders but remain limited in their ability to identify and classify non-coding variants, including intronic variants, cryptic splice-site alterations, and disruptions in regulatory regions. RNA sequencing (RNA-seq) has emerged as a powerful tool to bridge this gap by providing functional insights into genomic variants that disrupt splicing or gene expression, thereby aiding in variant interpretation and classification. We retrospectively reviewed 30 cases from the Utah Penelope Program and the Undiagnosed Diseases Network over a three-year period, in which RNA-seq was performed on whole blood and/or fibroblasts following either negative DNA sequencing or the identification of candidate variants requiring functional assessment. In these cases, RNA-seq identified exon skipping, cryptic splice-site activation, and intron retention, leading to transcript disruption. Additionally, positional enrichment analysis clarified X-inactivation patterns and dosage effects, confirming the pathogenicity of copy number variants. By detecting these transcript-level alterations, RNA-seq provided functional evidence supporting the reclassification of multiple variants of uncertain significance, contributing to diagnostic resolution in selected cases. This study underscores the clinical utility of RNA-seq in detecting splicing and regulatory defects that DNA sequencing and predictive tools alone cannot resolve. Integrating RNA-seq into clinical workflows can support variant classification, aid in diagnostic resolution for selected cases, and provide mechanistic insights into genetic disorders, contributing to patient care and genetic counseling.