Amyotrophic lateral sclerosis (ALS) is a devastating motoneuron disease characterized by sustained loss of neuromuscular junctions, degenerating corticospinal motoneurons and rapidly progressing muscle paralysis. Motoneurons have unique features, essentially a highly polarized, lengthy architecture of axons, posing a considerable challenge for maintaining long-range trafficking routes for organelles, cargo, mRNA and secretion with a high energy effort to serve crucial neuronal functions. Impaired intracellular pathways implicated in ALS pathology comprise RNA metabolism, cytoplasmic protein aggregation, cytoskeletal integrity for organelle trafficking and maintenance of mitochondrial morphology and function, cumulatively leading to neurodegeneration. Current drug treatments only have marginal effects on survival, thereby calling for alternative ALS therapies. Exposure to magnetic fields, e.g., transcranial magnetic stimulations (TMS) on the central nervous system (CNS), has been broadly explored over the past 20 years to investigate and improve physical and mental activities through stimulated excitability as well as neuronal plasticity. However, studies of magnetic treatments on the peripheral nervous system are still scarce. Thus, we investigated the therapeutic potential of low frequency alternating current magnetic fields on cultured spinal motoneurons derived from induced pluripotent stem cells of FUS-ALS patients and healthy persons. We report a remarkable restoration induced by magnetic stimulation on axonal trafficking of mitochondria and lysosomes and axonal regenerative sprouting after axotomy in FUS-ALS in vitro without obvious harmful effects on diseased and healthy neurons. These beneficial effects seem to derive from improved microtubule integrity. Thus, our study suggests the therapeutic potential of magnetic stimulations in ALS, which awaits further exploration and validation in future long-term in vivo studies.

We report an extensive high-field study of atacamite Cu 2 Cl ( OH ) 3 , a material realization of quantum sawtooth chains with weak interchain couplings, in continuous and pulsed magnetic fields up to 58 T. In particular, we have mapped the entropy landscape for fields as high as 35 T and have identified a field-induced quantum critical point at 21.9(1) T for H ∥ c axis. The quantum critical point separates field regions with and without magnetic order, evidenced by our thermodynamic study and H 1 nuclear magnetic resonance spectroscopy, but lies far below full saturation of the magnetization. Corroborated by numerical results using density-matrix renormalization group calculations, we find this behavior associated with a dimensional reduction of the spin system: the sawtooth chain effectively decouples into an antiferromagnetic spin- 1 / 2 chain (backbone of the sawtooth chain) in the presence of an exchange field produced by the remaining field-polarized spins. Published by the American Physical Society 2025

We report a random singlet ground state in the S = 1 2 Heisenberg pyrochlore antiferromagnet NaCdCu 2 F 7 . Cationic Na + / Cd 2 + disorder on the pyrochlore A site generates a broad distribution of Cu 2 + – F − – Cu 2 + exchange couplings, introducing intrinsic magnetic bond disorder. Despite strong antiferromagnetic interactions ( θ CW = − 72 K ) , no magnetic order or global spin freezing is observed in dc and ac susceptibility, specific heat, or Na 23 nuclear magnetic resonance to 120 mK, with muon spin relaxation experiments confirming persistent spin dynamics to 58 mK. T -linear specific heat, a Curie-like susceptibility tail, and power-law scaling with data collapse in χ ( T ) , M ( H ) , C mag / T , Na 23 ( 1 / T 1 T ) , and the muon spin polarization P ( t ) reveal a disorder-driven network of random singlets and orphan spins. Scaling across multiple bulk and local probes is consistent with a broad distribution of exchange energies, P [ J ] ∼ J − α . This behavior contrasts with previously studied Na A ″ B 2 F 7 pyrochlore fluorides, where magnetic bond disorder precipitates spin-glass freezing, underscoring the crucial role of strong S = 1 2 quantum fluctuations in NaCdCu 2 F 7 .

Within the family of altermagnets, CrSb is a metallic, collinearly ordered material that exhibits particularly strong symmetry-induced spin splitting in its band structure. In this study, we combine electrical magnetotransport measurements up to 68 T on microfabricated single-crystalline CrSb with first-principles calculations to investigate its Fermi surface. Notably, we study the temperature and field-orientation dependence of magnetic quantum oscillations observed in the magnetoresistance. The observed frequency spectrum agrees well with results from density functional theory calculations that take spin-orbit coupling into account, without invoking significant band shifts. Our results confirm the predicted electronic band structure of altermagnetic CrSb and highlight the importance of high magnetic fields for accurately mapping the Fermi surfaces of unconventional emergent materials.