Extreme-ultraviolet and X-ray jets occur frequently in magnetically open coronal holes on the Sun, especially at high solar latitudes. Some of these jets are observed by white-light coronagraphs as they propagate through the outer corona toward the inner heliosphere, and it has been proposed that they give rise to microstreams and torsional Alfvén waves detected in the solar wind. To predict and understand the signatures of coronal-hole jets, we have performed a detailed statistical analysis of such a jet simulated with an adaptively refined magnetohydrodynamics model. The results confirm the generation and persistence of three-dimensional, reconnection-driven magnetic turbulence in the simulation. We calculate the spatial correlations of magnetic fluctuations within the jet and find that they agree best with the Müller-Biskamp scaling model including intermittent current sheets of various sizes coupled via hydrodynamic turbulent cascade. The anisotropy of the magnetic fluctuations and the spatial orientation of the current sheets are consistent with an ensemble of nonlinear Alfvén waves. These properties also reflect the overall collimated jet structure imposed by the geometry of the reconnecting magnetic field. A comparison with Ulysses observations shows that turbulence in the jet wake is in quantitative agreement with that in the fast solar wind.
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http://dx.doi.org/10.3847/1538-4357/aa5cb9 | DOI Listing |
BMC Endocr Disord
January 2025
Department of Endocrinology, Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning, 110033, China.
Objective: Insulin resistance (IR) is often present in diabetes, which imposes a heavy burden on the prevention and treatment of diabetes. Triglyceride glucose index (TyG) is simple, reliable and reproducible in detecting IR, and has great advantages in predicting the risk of diabetes. The aim of this study was to analyze the potential association between TyG and the risk of diabetes in Chinese middle-aged and older adults using a prospective cohort study design.
View Article and Find Full Text PDFSci Rep
January 2025
Key Laboratory for Information Science of Electromagnetic Waves and the Research Center of Smart Networks and Systems, School of Information Science and Technology, Fudan University, Shanghai, 200433, China.
Addressing the shortcomings of the Sparrow Search Algorithm (SSA), such as low accuracy of convergence and tendency of falling into local optimum, a Multi-strategy Integrated Sparrow Search Algorithm (MISSA) is proposed. In this method, by improving the black-winged kite algorithm and applying it to the producer's position update formula, an improved search strategy (ISS) is firstly proposed to enhance search ability. Secondly, a new strategy inspired by the Coot algorithm, called the group follow strategy (GFS), is proposed to improve the ability to jump out of the local optimum.
View Article and Find Full Text PDFJ Epidemiol
January 2025
Department of Health Services Research, Institute of Medicine, University of Tsukuba.
BackgroundStudies have shown that informal caregiving is associated with an increased risk of cardiovascular diseases. However, there is limited evidence on the mechanisms involved. To fill this knowledge gap, we investigated the association of informal caregiving with changes in health-related behaviors.
View Article and Find Full Text PDFPhotodiagnosis Photodyn Ther
January 2025
Ningbo Eye Hospital, Wenzhou Medical University, Ningbo, Zhejiang, 315000, P.R. China. Electronic address:
Purpose: To evaluate the differences in fundus tessellation among various severities using multifocal visual electrophysiology (MfERG) and optical coherence tomography angiography (OCTA) for clinical grading and treatment.
Methods: This study included 52 patients totaling 87 eyes. The Early Treatment Diabetic Retinopathy Study (ETDRS) grid division method was utilized to assess Grade of fundus tessellation.
Arch Gerontol Geriatr
January 2025
Primary Care Research Centre, School of Primary Care, Population Sciences and Medical Education, University of Southampton, United Kingdom.
Background: Previous longitudinal studies have linked multimorbidity to loneliness (feeling alienated) and social isolation (having reduced social contact). However, the nature of these associations over time is unclear.
Objective: To examine bidirectional associations of multimorbidity with loneliness and social isolation over a 14-year follow-up in a nationally representative cohort of adults aged ≥ 50 years.
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