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We study electromagnetic ion cyclotron (EMIC) waves based on observations from the ionosphere, magnetosphere, and ground during a geomagnetic storm recovery phase on 28 August 2018. In this case, multiple ducting EMIC waves in the ionosphere show higher frequencies in the post‐midnight than those in the pre‐midnight. Ionospheric EMIC wave frequency differences in magnetic local time (MLT) are consistent with MLT frequency differences in the equatorial magnetosphere, which are mainly caused by different background magnetic field at different L‐shells. Moreover, we report the first observation of frequency range selections in ionospheric ducting EMIC waves and find that frequency selections depend on the magnetic field intensity in the main part of the ionospheric waveguide, with higher frequency corresponding to larger magnetic field. This study reveals the important role of background magnetic field in regulating ducting EMIC wave frequencies in the ionosphere. Plain Language Summary: Electromagnetic ion cyclotron (EMIC) waves are in the frequency range of 0.2–5 Hz, and they may occur in three different bands, which are named as H+, He+, and O+ bands from high to low frequencies. In this paper, He+ band EMIC waves in the nightside during a geomagnetic storm are observed by satellites in the ionosphere, and their frequencies are different, that is, frequencies are higher in the post‐midnight than those in the pre‐midnight. Ionospheric EMIC wave frequency differences in local time have been noticed before but have not yet been explained. We discover that ionospheric EMIC wave frequency differences in local time agree well with frequency differences in the magnetosphere. Besides frequency discrepancies in local time, in the post‐midnight, ionospheric EMIC waves tend to select higher or lower frequency range relative to frequencies in the magnetosphere. We find that these frequency selections mainly depend on the magnetic field intensity in the ionosphere. The frequency selections in ionospheric EMIC waves have not been identified before, and it is important to understand variations of EMIC waves in the ionosphere. Key Points: Ionospheric EMIC wave frequency differences in magnetic local time (MLT) are consistent with MLT frequency differences in the equatorial magnetosphereHigher/lower wave frequencies in the equatorial magnetosphere are at lower/higher L‐shells with larger/smaller background magnetic fieldFrequency selections of ducting EMIC waves depend on local magnetic field, and frequency is higher when the magnetic field is larger [ABSTRACT FROM AUTHOR]

Objective: This study was to investigate the role of hsa-miR-155-3p and hsa-miR-155-5p as biomarkers and regulators of biological behavior in Systemic Sclerosis. Methods: A total of 10 SSc patients and 10 healthy controls were selected for the study. The expression levels of hsa-miR-155-3p and hsa-miR-155-5p in peripheral blood mononuclear cells of SSc patients and healthy controls were measured using RT-qPCR. The diagnostic value of these miRNAs was explored using Receiver Operating Characteristic curve analysis. Pearson or Spearman correlation analysis was performed to assess the correlation between miRNAs and clinical indicators in SSc patients. Potential target genes of hsa-miR-155-3p and hsa-miR-155-5p were predicted using miRDB, Targetscan, and miRDIP databases. GO functional annotation, KEGG pathway enrichment analysis, protein-protein interaction network construction, and selection of central genes were conducted. Results: The expression levels of hsa-miR-155-3p and hsamiR- 155-5p were significantly higher in PBMCs of SSc patients compared to healthy controls (P<0.001). The ROC curve analysis showed that hsa-miR-155-3p and hsa-miR-155-5p had a high diagnostic value for SSc (AUC=1, P<0.001). Correlation analysis revealed that hsamiR- 155-3p, hsa-miR-155-5p, and clinical indicators such as high-resolution CT, neutrophil percentage, lymphocyte percentage, and albumin to globulin ratio were correlated (P<0.05). The signaling pathways enriched with target genes of hsa-miR-155-3p and hsa-miR-155- 5p were closely associated with the occurrence and development of SSc fibrosis, immunity, and inflammation. Conclusions: hsa-miR-155-3p and hsa-miR-155-5p may be involved in regulating the occurrence and development of SSc fibrosis, immunity, and inflammation. They have the potential to serve as biomarkers for clinical diagnosis and treatment of SSc. [ABSTRACT FROM AUTHOR]

Objective: The apoptotic signaling pathway is obviously disordered in systemic lupus erythematosus (SLE). Natural IgM (nIgM) is important in clearing apoptotic cells and preventing them from triggering deleterious autoimmunity. B-1 and innate-like B (ILBs) cells are the main nIgM producers. Human CD27+IgD+ B cells (un-switched memory B cells) are considered ILBs. However, their functional properties in SLE remain undefined. Methods: Peripheral blood sample of 50 SLE patients and 50 healthy controls were collected, and twelve SLE patients were assessed in a follow-up study. The amount of CD27+IgD+ B cell in each population was analyzed by flow cytometry. The IgM and IL-10 levels of CD27+IgD+ B cell were assessed by ELISPOT and qRT-PCR, respectively. SPSS 17.0 (SPSS, USA) was employed for data analysis. P < 0.05 indicated statistical significance. Result: The amounts of CD27+IgD+ B cell were significantly decreased in SLE patients than healthy control (P < 0.01). CD27+IgD+ B cell amounts were positively correlated with WBC (r = 0.337, P = 0.017), platelet count (r = 0.396, P = 0.004), and serum C3 levels (r = 0.415, P = 0.003) and negatively correlated with serum creatinine levels (r = − 0.285, P = 0.045), SLEDAI(r = − 0.724, P = 0.000), and anti-dsDNA(r = − 0.477, P = 0.000). The IgM and IL-10 levels of CD27+IgD+ B in active SLE were decreased than healthy control (P < 0.001). Moreover, CD27+IgD+ B cells are increased in SLE cases after treatment than before treatment (P < 0.001). Conclusion: The amounts of CD27+IgD+ B cell were significantly decreased in SLE patients compared with the healthy population, and CD27+IgD+ B cell was verified to be correlated with clinical and immunological features in SLE patients. CD27+IgD+ B cells had impaired function associated with IgM and IL-10 production in active SLE. Moreover, the amounts of CD27+IgD+ B cells were recovered to the normal level in SLE cases with treatment-related disease remission. Key Points • CD27+IgD+B cell amounts are significantly decreased in SLE patients than healthy control. • CD27+IgD+B cells are functionally impaired in producing natural antibody-like IgM and IL-10 in SLE patients. • CD27+IgD+B cell amounts are correlated with clinical and immunological features in SLE. [ABSTRACT FROM AUTHOR]

The terrestrial magnetosphere is perpetually exposed to and significantly deformed by the interplanetary magnetic field (IMF) in the solar wind. This deformation is typically detected at discrete locations by space‐ and ground‐based observations. Earth's aurora, on the other hand, is a globally distributed phenomenon that may be used to elucidate magnetospheric deformations caused by IMF variations, as well as plasma supply from the deformed magnetotail to the high‐latitude atmosphere. We report the utilization of an auroral form known as the transpolar arc (TPA) to diagnose the plasma dynamics of the globally deformed magnetosphere. Nine TPAs examined in this study have two types of a newly identified morphology, which are designated as "J"‐ and "L"‐shaped TPAs from their shapes and are shown to have antisymmetric morphologies in the Northern Hemisphere and Southern Hemisphere, depending on the IMF polarity. The TPA‐associated ionospheric current profiles suggest that electric currents flowing along the magnetic field lines (field‐aligned currents [FACs]), connecting the magnetotail and the ionosphere, may be related to the "J"‐ and "L"‐shaped TPA formations. The FACs can be generated by velocity shear between fast plasma flows associated with nightside magnetic reconnection and slower background magnetotail plasma flows. Complex large‐scale TPA FAC structures, previously unraveled by an magnetohydrodynamic (MHD) simulation, cannot be elucidated by our observations. However, our interpretation of TPA features in a global context facilitates the usage of TPA as a diagnostic tool to effectively remote sense globally deformed terrestrial and planetary magnetospheric processes in response to the IMF and solar wind plasma conditions. Plain Language Summary: In magnetospheric physics, the aurora is one of the most important phenomena in qualitatively and quantitatively understanding the transfer of plasma and energy from the solar wind to the high‐latitude atmosphere via terrestrial and other planetary magnetospheres. To understand the global picture of the plasma supply from the terrestrial magnetosphere, deformed by the interplanetary magnetic field (IMF) in the solar wind, to the auroral zone, the formation process of a new morphology of auroral transpolar arc (TPA) is investigated in this study. The source of these TPAs can be the electric currents flowing along magnetic field lines, induced by the plasma flows in the magnetosphere. The conventional TPA has a straight bar shape, which connects the nightside and dayside of the auroral oval. The new TPA morphologies, on the other hand, have significant "distortions" toward premidnight and postmidnight at their nightside ends, which may be caused by magnetic field line twisting and magnetosphere deformations due to the action of the IMF. Our results facilitate a paradigm shift in understanding the implications of TPA structure on global‐scale dynamics in the deformed magnetosphere, and as such, the usage of the auroral TPA shape as a tool to diagnose global‐scale magnetospheric effects. Key Points: A new morphological type of transpolar arc, characterized by large nightside distortions in the premidnight or postmidnight sector, is describedNightside reconnection and magnetotail deformation by IMF penetration play essential roles in the formation of nightside distorted TPANightside distorted TPAs can be used as a remote‐sensing tool to diagnose globally IMF‐deformed magnetospheric processes [ABSTRACT FROM AUTHOR]

The optimum combination of antioxidants used for stabilization of flaxseed oil and extension of its shelf life was examined. To achieve this goal, based on different antioxidant mechanisms, a combination of four types of antioxidants including tocopherol, ascorbyl palmitate (AP), phytic acid (PA), and a source of polyphenol (antioxidant of bamboo leaves (AOB), rosemary extract (RE), tea polyphenols extract (TP), and tea polyphenol palmitate (TPP)) were added to flaxseed oil. The effects were monitored using peroxide value (POV), thiobarbituric acid‐reactive substances (TBARS), free radicals, and Rancimat induction time (RIT) of flaxseed oil during accelerated storage. Flaxseed oil containing 80 mg/kg tocopherol, 40 mg/kg AP, 40 mg/kg PA, and 240 mg/kg TPP was found to be more stable to oxidation than other samples and had 3.22‐fold longer shelf life than that of the control flaxseed oil. Practical applications: Due to its high concentration of alpha‐linolenic acid, flaxseed oil is prone to oxidation. To improve the oxidative stability of flaxseed oil and prolonging its shelf life, the optimum formulation and ratio of mixtures of antioxidants with different antioxidant mechanisms were studied. Our results indicated that the flaxseed oil containing 80 mg/kg tocopherol, 40 mg/kg AP, 40 mg/kg PA, and 240 mg/kg TPP was very stable to oxidation. And the shelf life of the flaxseed oil containing this optimum mixture of antioxidants was 3.22‐fold longer than that of the control flaxseed oil. Therefore, adding the optimum mixture of antioxidants will help to produce the flaxseed oil products with better oxidative stability for commercial development. [ABSTRACT FROM AUTHOR]