Recent publications
A 33T cryogen-free superconducting magnet (33TCSM) project is now in progress at HFLSM, IMR, Tohoku University. The 33T-CSM consists of a f 68mm- 19 T REBCO (HTS) insert and a f 320mm-14 T CuNb/Nb3Sn and NbTi Rutherford (LTS) magnets. The 33T-CSM system has been installed and tested without the HTS insert in March 2024. The LTS outsert magnet consists of three CuNb/Nb3Sn Rutherford cable coils and two NbTi Rutherford cable coils with an epoxy impregnation. It can generate 14 T in a 320 mm bore with 879 A. This winding makes use of advanced high strength CuNb/ Nb3Sn strands specifically developed for the 33T-CSM project, enabling high stress design with about 275 MPa in the Nb3Sn coil at 14 T. The 19 T-HTS insert is designed based on the robust REBCO coil technology we proposed in previous works. For the cooling system, a 9W GM/JT cryocooler is used for the LTS coils, four 4K-GM cryocoolers cool the REBCO coils (1.5 W each at 4.2 K) and two single-stage cryocoolers are used for the radiation shield and current leads. Helium circulation with compressors ensure the thermal connection between the coils and the cryocoolers. The initial cooling is about 7.3 days from room temperature. The test of the 14 T LTS magnet was successfully completed up to 839 A with the nominal maximum electromagnetic stress of 275 MPa after one training quench.
A 33 T cryogen-free superconducting magnet (33 T-CSM) is under development. The 33 T-CSM consists of a REBCO insert coil and Nb3Sn/NbTi outsert coils. The REBCO insert coil is designed to generate 19 T in the external field of 14 T. The REBCO insert coil is composed of stacked 64 single pancake coils wound with two bundled REBCO tapes. The inner and outer diameters of the REBCO insert coil are 68 mm and 295 mm, respectively. The REBCO coil is impregnated with epoxy resin for conduction cooling. To prevent delamination of the superconducting layer by thermal stress, the fluorine-coated polyimide tape is co-wound with REBCO tapes and to prevent degradation of superconductivity by electromagnetic stress, reinforcing tape is also co-wound. According to 2D-FEM, it is shown that the circumferential strain ϵθ under applying electromagnetic force is 0.29%. The results of 2D-FEM also suggest that stress concentration occurs at the connection between the coil and the bus bar, and at the widthwise end of the REBCO tape. In this paper, the basic design of the insert coil and the results of FEM analysis will be described.
In this study, the synchronization ability of vortex‐based spin‐torque nano‐oscillators is investigated for three different dynamical regimes: the fundamental gyrotropic mode, the dynamic C‐state, and the transition regime characterized by stochastic switching between the gyrotropic mode and the dynamic C‐state. By combining injection locking at 2f and mutual synchronization experiments between two oscillators, it is shown that the ability to synchronize is larger in the transition regime than in the gyrotropic mode. By slightly tuning the injected dc current, this transition regime, which is highly efficient at synchronization, evolves into a dynamic state with no ability to synchronize. Thus, the synchronization range can be tuned, and the synchronized state can be easily switched on and off by selecting the dynamic regime. These results are promising for applications requiring large‐scale networks of synchronized oscillators, where tuning the synchronization range and controlling the synchronized state are important features, such as neuromorphic computing and broadband microwave communication
Understanding the hydromechanical behavior of porous media such as sandstones is critical to various geoengineering applications such as geologic carbon storage, geothermal projects, oil and gas production and environmental remediation in aquifers. In these contexts, accurate quantification of the constitutive hydromechanical behavior of sandstones is necessary to predict reservoir responses. In this work, neutron tomography data were acquired during coupled triaxial-flow tests on Idaho Gray sandstone cores to characterize the full-field hydromechanical response. The hydromechanical response was then correlated to macroscopic observations obtained at the sample boundaries and to the initial natural microstructural heterogeneity characterized using high-resolution X-ray tomography. The flow tests involved saturating samples with D2O and performing volume-driven H2O injection, with rapid (1-min) neutron in situ tomography. Digital volume correlation (DVC) on high-resolution neutron tomography data enabled tracking of 3D strain evolution describing the mechanical deformation. Neutron tomography data acquired during the permeability tests enabled 4D (3D + time) fluid flow analysis, revealing heterogeneous percolation paths. The comparison of the initial porosity and strain fields indicated that sample porosity heterogeneity influenced both strain evolution and shear band localization. Additionally, a relationship was identified between the evolution of the fluid flow field and the strain field. Notably, changes in percolation paths correlated with the evolution of the volumetric strain field.
- Martí Ninot-Pedrosa
- Gyula Pálfy
- Hafez Razmazma
- [...]
- Lauriane Lecoq
- Éric Toussirot
- André Ramon
- Caroline Laheurte
- [...]
- Philippe Saas
Objective
mucosal-associated invariant T cells (MAIT) have been involved in the pathophysiology of axial spondyloarthritis (axSpA). We aimed to further investigate the phenotype of circulating MAIT cells in patients with axSpA by assessing the expression of an activation marker and gut homing receptors as well as the impact of TNF-α blockade. The presence of MAIT cells in synovial biopsies from axSpA patients was also studied.
Methods
blood samples were obtained from 26 axSpA patients (11 radiographic, 15 nonradiographic) and 27 healthy controls (HC). Frequency of Vα7.2+CD161+ MAIT cells was determined in axSpA and HC. Expression of CD69, CCR9 and CD49d on MAIT cells was analyzed by flow cytometry. The presence of MAIT cells was examined in synovial biopsy samples from three axSpA patients and compared to synovial biopsies from 3 rheumatoid arthritis (RA) patients and 4 osteoarthritis (OA) patients by confocal microscopy.
Results
patients with axSpA were characterized by a higher frequency of CD3+ and CD8+ MAIT cells expressing CD69, CCR9 and CD49d, especially in the radiographic subgroup. MAIT cells were detected in a synovial biopsy sample from one patient with axSpA. After TNF-α blockade, a decrease in the frequency of MAIT cells and TNF-α/IL-17A – producing-MAIT cells was observed.
Conclusion
MAIT cells were activated and expressed gut homing receptors, indicating their potential involvement in the gut-joint axis of axSpA. MAIT cell frequency and function were reduced by TNF-α blockade. MAIT cells could be found in synovial tissue in axSpA.
- T Coudert
- A Delphin
- A Barrier
- [...]
- T Christen
Bio-based surfactants, derived from microbial fermentation, are appealing biocompatible amphiphiles traditionally employed in depollution, pest control, personal care, cosmetics, and medicine, their potential in biomedical scaffolds remains largely unexplored due...
Ge-rich Ge–Sb–Te alloys exhibit a high (>350 °C) crystallization temperature, which is compatible with applications requiring a high thermal stability such as the use of non-volatile memories in cars. As the composition of these alloys does not correspond to any stable crystalline phase, crystallization from the amorphous phase is accompanied by phase separation (Ge2Sb2Te5 + Ge). The complexity of the elemental processes associated with this multiphase amorphous-to-crystal transition calls for in-depth materials studies. In this work, we focus on the influence of a thin (5 nm) underlayer (Ge2Sb2Te5 or Sb2Te3) on the crystallization of a Ge-rich Ge–Sb–Te alloy. Using in situ synchrotron x-ray diffraction, we demonstrate that the underlayers facilitate crystallization by decreasing crystallization temperature and suppressing incubation time. These results are interpreted in the framework of classical nucleation theory and are supported by crystallographic texture measurements, which evidence ⟨ 111 ⟩ fiber texture in the crystallized cubic Ge2Sb2Te5, particularly marked in the case of an Sb2Te3 underlayer. These results bear important consequences for the cycling of memory cells based on these materials.
Antarctic sea ice has changed significantly over the past four decades; yet limited understanding of fundamental processes, including its seasonal cycle, hinders our ability to interpret these changes. Here, we examine the processes determining the moment when sea ice locally disappears each spring, defined as the retreat date, using satellite observations over 1994–2020. We find that climatological retreat date is driven by sea ice melt in most of the seasonal ice zone and strongly constrained by the seasonal maximum ice thickness. Ice removal due to drifting ice export predominantly drives retreat only in coastal polynyas. At interannual timescales, retreat date anomalies are also preconditioned by prior maximum ice thickness, which affects melt‐driven spring ice loss through the ice‐albedo feedback, though this effect appears limited to specific regions. Winds emerge as a primary driver of interannual variability in the retreat date, influencing both drift‐ and melt‐related spring ice removal processes.
This study explored the synergistic potential of periodate-oxidized cellulose nanocrystals (CNCs) decorated with silver nanoparticles (AgNPs) to enhance the antimicrobial and mechanical properties of poly(vinyl alcohol) (PVA) and poly(l-lactic acid) (PLLA) biopolymer matrices. A concentration-dependent antibacterial activity was demonstrated against both Gram+ and Gram– bacteria, highlighting the potential of CNCs-AgNPs in inhibiting pathogenic strains. Moreover, the tensile strength of PVA and PLLA films was notably improved by incorporating CNCs-AgNPs. The filler demonstrated significant inhibitory effects on bacterial growth in chicken meat samples wrapped in PVA/CNCs-AgNPs nanocomposite films, allowing for an extension of the meat shelf life beyond acceptable microbiological limits. These results highlight the versatile capabilities of CNCs-AgNPs in polymer nanocomposites, positioning them as potent agents for antimicrobial packaging and as contenders for sustainable and functional nanomaterials in various applications.
Emerging evidence suggests that exposure to air pollutants and road traffic noise triggers stress responses, which mediate physiological responses in multiple organs and tissues. However, epidemiological study in children is sparse. We aimed to evaluate whether outdoor air pollution and road traffic noise are associated with physiological response measured by allostatic load in children. We studied 919 children aged 6–11 years from the HELIX (Human Early Life Exposome) cohort in 6 European countries with 19 biomarkers assessed in four physiological systems—cardiovascular, metabolic, immune/inflammation, and neuroendocrine systems. We then calculated both count-based and continuous scores for each physiological system and generated allostatic load scores (range 0–19). Exposure to air pollution (NO2, PM2.5, PM10, PM2.5absorbance) and road traffic noise (LDEN) based on participants’ home, school, and commuting route addresses were estimated for the year prior to outcome assessment. Higher exposure to all air pollutants was associated with a higher allostatic load, although only the association of PM10 survived correction for multiple testing (for count-based allostatic load score: RR = 1.27, 95%CI: 1.08, 1.48; for continuous allostatic load score: β = 0.56, 95% CI: 0.27–0.84, per each 10 µg/m³ increase in PM10). Examining physiological systems separately, higher exposure to air pollution was mainly associated with higher allostatic load in the immune/inflammatory and metabolic systems. No associations between road traffic noise and allostatic load were observed. Our findings suggest that air pollution act as a chronic stressor in manifesting multi-systemic physiological dysregulation in childhood, which may be a precursor of air pollution-related diseases.
Background
T cells play a crucial role in adaptive immunity, as they monitor internal and external immunogenic signals through their specific receptors (TCRs). Using high-throughput sequencing, one can assess TCR repertoire in various clinical settings and describe it quantitatively by calculating a diversity index. Multiple diversity indices that capture the richness of TCRs and the evenness of their distribution have been proposed in the literature; however, there is no consensus on gold-standard measures and interpretation of each index is complex. Our goal was to examine the performance characteristics of 12 commonly used diversity indices in simulated and real-world data.
Results
Simulated data were generated to evaluate how data richness and evenness affect index values using three nonparametric models. Fourteen real-world TCR datasets were obtained to examine differences in indices by analysis protocols and test their robustness to subsampling. Pielou, Basharin, d50, and Gini primarily describe evenness and highly correlate with one another. They are best suited for measuring the representation of TCR clones. Richness is best captured by S index, next Chao1 and ACE which also consider information on evenness. Shannon, Inv.Simspon, D3, D4, and Gini.Simpson measure richness and increasingly more information on evenness. More skewed TCR distributions provided more stable results in subsampling. Gini-Simpson, Pielou, and Basharin were the most robust in both simulated and experimental data.
Conclusions
Our results could guide investigators to select the best diversity index for their particular experimental question and draw attention to factors that can influence the accuracy and reproducibility of results.
Background
T-cell acute lymphoblastic leukemia (T-ALL) is a relatively rare hematological malignancy, characterized by the uncontrolled proliferation of immature T lymphoblasts and associated with a generally unfavorable prognosis. Our previous research has demonstrated that decreased mitochondrial activity is associated with the aggressiveness of T-ALL tumors. However, the mechanisms underlying this phenomenon and its contribution to treatment resistance remain largely elusive.
Methods
We have built up the largest known T-ALL tumor bank, with a median follow-up of 32 months, including our transcriptomic data from 79 newly sequenced tumors that adds to the 54 publicly accessible samples. Computational analyses and a series of functional assays were performed to investigate the molecular links between altered mitochondrial activity and drug resistance.
Results
The transcriptomic analysis revealed that down-regulation of mitochondrial activity is a potent driver of ABCB1 activation, a gene strongly associated with multidrug resistance. In tumors with low mitochondrial activity, the impaired fatty acids β-oxidation leads to intracellular lipid accumulation, which is directly involved in ABCB1 activation. Indeed, our data show that lipid neo-synthesis and accumulation promotes the activation of lipogenic transcription factors, liver X receptors (LXRs), which act as drivers of ABCB1 expression. Tumor data analyses confirmed that high ABCB1 expression in tumour samples is indeed associated with reduced mitochondrial gene expression, lipid droplet enrichment, increased tumour aggressiveness, and significantly shorter patient survival.
Conclusions
Our study demonstrates that reduced mitochondrial activity drives multidrug resistance in adult T-ALL via lipid-mediated activation of ABCB1. These findings enhance our understanding of the biology of aggressive T-ALL and provide insight into mechanisms of resistance to conventional chemotherapy. Consequently, we propose that targeting de novo lipogenesis and restricting dietary fats, such as caprylic acid, may help overcome treatment resistance in patients with T-ALL exhibiting low mitochondrial activity.
Trial registration
The clinical trial was registered under the identifiers ChiCTR-ONRC-14004968 and ChiCTR2000031553 at ClinicalTrials.gov.
Systems with pronounced spin anisotropy are pivotal in advancing magnetization switching and spin-wave generation mechanisms that are fundamental to spintronic technologies. Quasi-van der Waals ferromagnets like Cr1+δTe2 represent seminal materials in this field, renowned for their delicate balance between frustrated layered geometries and magnetism. Despite extensive investigation, the nature of their magnetic ground state and the mechanism of spin reorientation under external fields and varying temperatures remain contested. Here, we exploit complementary techniques to reveal a previously overlooked magnetic phase in Cr1+δTe2 (δ = 0.25 − 0.50), which we term orthogonal-ferromagnetism. This phase consists of atomically sharp single layers of in-plane and out-of-plane maximally canted ferromagnetic blocks, which differs from the stacking of multiple heterostructural elements required for crossed magnetism. Contrary to earlier reports of gradual spin reorientation in CrTe2-based systems, we present evidence for abrupt spin-flop-like transitions. This discovery further highlights Cr1+δTe2 compounds as promising candidates for spintronic and orbitronic applications, opening new pathways for device engineering.
Dispersal is a ubiquitous phenomenon that affects the dynamics of the population and the evolution of natural populations; however, it is challenging to measure in most species. Furthermore, the influence of informed dispersal behaviors, referring to the nonrandom selection of breeding habitats by individuals, on species' responses to rapid global change is substantial but difficult to comprehend. Here, we present a modeling framework to assess the dispersal characteristics and behaviors of a metapopulation when observations provide information on its neutral genetic structure for a restricted sampling of locations. Our mechanistic‐statistical model couples a deterministic model capturing the spatio‐temporal dynamics of four genetic clusters across all breeding colonies by integrating demographic processes with genetic projections, with a probabilistic observation model describing the probability to sample an individual from a given genetic cluster. We apply this new framework to the emperor penguin, a species living in Antarctica and currently experiencing habitat loss. The model estimates the species' dispersal distance, rates of emigration, and behaviors associated with dispersal (informed or random). By incorporating these estimations with satellite censuses of breeding colonies, we can identify environmental and demographic factors that influence the dispersal of emperor penguins. Finally, we provide new global population forecasts for emperor penguins that can inform conservation actions in Antarctica.
In the era of Big Data, the development of artificial intelligence (AI) systems presents both opportunities and challenges, particularly concerning privacy and fairness. While differential privacy (DP) has emerged as a robust methodology for preserving privacy in real-world applications, its local variant (LDP) specifically addresses trust issues by removing the reliance on a centralized server. Equally critical, conducting fairness audits of AI systems helps identify and mitigate discriminatory outcomes in machine learning. Although the relationship between DP and fairness is inherently multifaceted, this paper offers a detailed empirical examination of how collecting multi-dimensional sensitive attributes under LDP affects fairness in binary classification tasks. Our findings reveal that LDP can slightly improve fairness without substantially degrading model performance—challenging the notion that DP necessarily exacerbates unfairness. We demonstrate these results by evaluating seven state-of-the-art LDP protocols on three benchmark datasets, using established group fairness metrics. Moreover, we propose a novel privacy budget allocation scheme that incorporates varying domain sizes of sensitive attributes, achieving a superior privacy–utility–fairness trade-off compared to existing solutions.
Recent advancements in organic photovoltaics (OPVs) have focused on improving both efficiency and mechanical robustness, yet critical insights into the structural and mechanical properties of the materials remain underexplored, particularly in the context of intrinsically stretchable OPVs. These devices hold great promise for applications in wearable and portable electronics, offering exciting possibilities for energy generation in innovative use cases. This study presents novel findings on the structural and mechanical behavior of PM6:Y12 blends, processed using a green solvent and two deposition techniques: spin‐coating and blade‐coating. We demonstrate that the blade‐coating technique, performed in air, results in more ordered blend layers, with a significant increase in crystalline domain size from 67 Å to 136 Å. Additionally, we examine the effects of annealing and focus on the behavior of as‐cast blend layers. In an original approach, we studied the mechanical response of these films by in situ GIXRD under tensile strain on stretchable TPU/PEDOT:PSS substrates, revealing that the as‐cast PM6:Y12 blend can sustain up to 7% tensile strain. These findings provide valuable insights into the structural and mechanical properties of PM6:Y12 blends, providing a pathway for the development of stretchable OPVs.
Considered as an indicator of good mental health contributing to positive behaviors, self-esteem is impacted by body perception. Obesity is a risk factor for the development of low self-esteem, particularly among women. Age also plays a protective role in both the healthy population and those living with obesity. Since the relationship between self-esteem and BMI does not appear to evolve linearly, the aims of this study were (1) to analyze the link between BMI classes and global, multidimensional, and physical self-esteem, and (2) to identify a potential moderating effect of age. Global, multidimensional, and physical self-esteem were assessed using French versions of RSE, MSE and PSPP scales respectively in 454 women aged 18 to 75 stratified into five BMI groups: healthy weight, overweight, obesity class I, II and III. Global, multidimensional, and physical self-esteem appear to be related to BMI classes. Healthy weight women had significantly higher emo-
tional, professional, physical domains and subdomains self-esteem scores than those in obesity class I, II or III. “Tipping points” associated with reaching a BMI threshold at which scores of self-esteem stabilize have been high-lighted. These appeared at obesity class I and II, respectively, for the emotional and physical domains of self-esteem, and at overweight and obesity class II, respectively, for the physical strength and attractive body physical subdomains. Results also revealed a protective moderating effect of age on the relationship between BMI and physical self-esteem, and its subdomains. Obesity intervention programs should consider self-perceptions.
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