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Background: Electroacupuncture (EA) has been shown to promote functional recovery after cerebral ischemia–reperfusion (I/R) injury. However, the contribution of mitochondrial dynamics to recovery remains unclear. The aim of this study was to investigate whether mitochondrial dynamics are involved in the effects of EA on cerebral I/R injury. Methods: The rats with cerebral I/R injury were established by the middle cerebral artery occlusion/reperfusion. Subsequently, EA was applied to Baihui (GV20) and Dazhui (GV14) acupoints, with 2 Hz/5 Hz in frequency, 1.0 mA in intensity, 20 min each time, once a day for seven consecutive days. The therapeutic outcomes were assessed by modified neurological severity score (mNSS), 2,3,5-Triphenyte-trazolium chloride (TTC) staining, and hematoxylin-eosin (HE) staining. Mitochondrial morphology was observed under transmission electron microscopy. Adenosine triphosphate (ATP) content and ATP synthases (ATPases) activity were evaluated to measure mitochondrial function using ELISA. Finally, mitochondrial dynamics-related molecules, including dynamin-related protein 1 (Drp1), fission 1 (Fis1), mitofusin 1 (Mfn1), mitofusin 2 (Mfn2), and optic atrophy 1 (OPA1), were detected by Western blot and immunofluorescence staining. Results: Cerebral I/R injury induced neurological dysfunction, cerebral infarction and neuronal injury, all of which were ameliorated by EA. And EA improved mitochondrial morphology and function. Moreover, EA altered the balance of mitochondrial dynamics. Specifically, the data showed a significant decrease in the expression of Drp1 and Fis1, leading to the inhibition of mitochondrial fission. Additionally, Mfn1, Mfn2 and Opa1, which are related to mitochondrial fusion, were effectively promoted after EA treatment. However, sham EA did not show any neuroprotective effects in rats with cerebral I/R injury. Conclusions: In summary, our study indicates that the balance of mitochondrial dynamics is crucial for EA therapy to treat cerebral I/R injury.

With Solar Orbiter (SO) being put into successful operational observation, solar magnetic observation has entered the era of remote sensing from dual view points. In this paper, we carried out a simulation of correcting the 180 ∘ ambiguity of transverse magnetic field with magnetograms from dual view points using an analytical formula as well as the observations made by the Helioseismic and Magnetic Imager (HMI). Magnetograms of a small mature sunspot at different times were used to simulate magnetograms from dual view points. We find that in order to correct the 180 ∘ ambiguity of the vector magnetograms, it is sufficient to have a line-of-sight magnetogram from another view point to help to judge the direction of the transverse magnetic field. For the measuring accuracy of HMI, we estimate that a ∼ 30 ∘ angle formed from two observational points is the smallest angle to correct the 180 ∘ ambiguity around the place with the magnetic field strength of < 50 Gs. Correction for weaker magnetic fields surely needs larger separation angles, but considering projection effect, we propose that separation angles of ∼ 30 ∘ are the optimal angles for future space missions with the scientific aim of correcting the 180 ∘ ambiguity of vector magnetograms. [ABSTRACT FROM AUTHOR]