Tract-specific magnetization transfer ratio provides insights into the severity of degenerative cervical myelopathy
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Noncollinear spin texture-driven torque in deterministic spin–orbit torque-induced magnetization switching
To reveal the role of chirality on field-free spin–orbit torque (SOT) induced magnetization switching, we propose an existence of z-torque through the formation of noncollinear spin texture during SOT-induced magnetization switching in a laterally two-level perpendicular magnetic anisotropy (PMA) system. For the investigation of torque, we simulate magnetization dynamics in the two-level PMA system with SOT, which generates the noncollinear spin texture. From the spatial distribution of magnetic energy, we reveal the additional z-directional torque contribution in the noncollinear spin texture, which is unexpected in the conventional SOT-induced magnetization switching in collinear spin texture. The z-directional torque originates from the interaction between the chirality of the noncollinear spin texture and the interfacial Dzyaloshinskii-Moriya interaction of the system. Furthermore, the experimental observation of the asymmetric magnetization switching to the direction of the current flow in the two-level PMA system supports our theoretical expectation.
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Is neck pain a marker for something serious? Like myelopathy
Degenerative Cervical Myelopathy (DCM) is a chronic progressive condition of the cervical spine that leads to compression of the spinal cord. It is the most common cause of spinal cord dysfunction in adults, and it occurs due to age-related changes or genetically associated pathologies. DCM is a clinical and radiological diagnosis and presents with a spectrum of symptoms ranging from neck pain and stiffness to paralysis. While neck pain is prevalent amongst patients attending specialist clinics, its predictive value for DCM is limited. This paper focuses on elucidating the relationship between DCM and chronic neck pain, and we discuss the underlying aetiology and broader neurological implications in the context of the literature. The progression of DCM can be slow and insidious with symptoms worsening gradually over time. Neck pain should not be discounted in the evaluation of DCM.
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