Propagation of auto-focusing hypergeometric Gaussian beams along a slant path in oceanic turbulence.

Compared to horizontal transmission, the oceanic dissipation rate and temperature-salinity distribution ratio are no longer constant but vary with depth, imposing greater complexity on oceanic turbulence when beams propagate through a slant path and resulting in more limitations on the performance of underwater wireless optical communication (UWOC) links. This study focuses on investigating the performance, especially the auto-focusing characteristic, of auto-focusing hypergeometric Gaussian (AHGG) beams propagating along slant paths in oceanic turbulence. We theoretically derive the spatial coherence radius and the relative probability of the orbital angular momentum (OAM) mode for AHGG beams passing through such links. Numerical simulations reveal that AHGG beams exhibit superior propagation performance compared to hypergeometric Gaussian beams. Lower beam orders and OAM numbers contribute to improved performance, while careful selection of auto-focusing length can tangibly enhance detection performance as well. Additionally, tidal velocities and wind speeds have nonnegligible effects on OAM signal probability. Our results further demonstrate that surface buoyancy flux, temperature gradients, and waterside friction velocity significantly affect beam transmission under varying wind conditions. These findings, particularly controlling the auto-focusing length of AHGG beams to match the transmission distance, provide valuable insights for enhancing the quality of UWOC links.

Pharmacodynamics and mechanism of Erigeron breviscapus granules in the treatment of ischemic stroke in mice by regulating sphingolipid metabolism based on metabolomics.

AIM: Erigeron breviscapus (Vant.) Hand.-Mazz. (EB) granules is the extract preparation of EB, with clear curative effect and unclear mechanism. This study intends to systematically explore the specific mechanism of EB granules in the treatment of IS from the metabolic perspective. METHODS: The model of transient middle cerebral artery occlusion (tMCAO) in mice was established by the suture-occluded method. The therapeutic effect of EB granules on tMCAO mice was evaluated by behavioral evaluation, brain water content determination, 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining, and levels of lactate dehydrogenase (LDH) and neuron specific enolase (NSE) in serum. In order to screen differential metabolites, non-targeted metabolomics technology was used to detect the metabolites in serum before and after administration. Univariate statistics, multivariate statistics and bioinformatics were used to analyze the changes of metabolites in serum of tMCAO mice. The possible related mechanism of EB granules in treating IS was screened by pathway enrichment analysis, and the preliminary verification was carried out at animal level by enzyme linked immunosorbent assay (ELISA) and western blot (WB). RESULTS: EB granules could significantly improve behavior of tMCAO mice, reduce brain water content and cerebral infarction volume, improve morphology of brain tissue, reduce the levels of LDH and NSE in serum. A total of 232 differential metabolites were screened, which were mainly enriched in many biological processes such as sphingolipid metabolism. The differential metabolite S1P and its receptors S1PR1 and S1PR2 in sphingolipid metabolism were verified. The results showed that the level of S1P in brain tissue increased and the protein expression of S1PR1 decreased significantly after modeling, and reversed after administration, but there was no significant difference in the protein expression of S1PR2. CONCLUSION: The therapeutic effects of EB granules may be related to affecting sphingolipid metabolism through regulating S1P/S1PR1.

Pharmacodynamics and Mechanism of Astragali Radix and Anemarrhenae Rhizoma in Treating Chronic Heart Failure by Inhibiting Complement Activation.

Astragali radix (AR) and anemarrhenae rhizoma (AAR) are used clinically in Chinese medicine for the treatment of chronic heart failure (CHF), but the exact therapeutic mechanism is unclear. In this study, a total of 60 male C57BL/6 mice were divided into 5 groups, namely sham, model, AR, AAR, and AR-AAR. In the sham group, the chest was opened without ligation. In the other groups, the chest was opened and the transverse aorta was ligated to construct the transverse aortic constriction model. After 8 weeks of feeding, mice were given medicines by gavage for 4 weeks. Left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were detected by echocardiography. Heart weight index (HWI) and wheat germ agglutinin staining were used to evaluate cardiac hypertrophy. Hematoxylin-eosin staining was used to observe the pathological morphology of myocardial tissue. Masson staining was used to evaluate myocardial fibrosis. The content of serum brain natriuretic peptide (BNP) was detected by enzyme-linked immunosorbent assay kit. The content of serum immunoglobulin G (IgG) was detected by immunoturbidimetry. The mechanism of AR-AAR in the treatment of CHF was explored by proteomics. Western blot was used to detect the protein expressions of complement component 1s (C1s), complement component 9 (C9), and terminal complement complex 5b-9 (C5b-9). The results show that AR-AAR inhibits the expression of complement proteins C1s, C9, and C5b-9 by inhibiting the production of IgG antibodies from B cell activation, which further inhibits the complement activation, attenuates myocardial fibrosis, reduces HWI and cardiomyocyte cross-sectional area, improves cardiomyocyte injury, reduces serum BNP release, elevates LVEF and LVFS, improves cardiac function, and exerts myocardial protection.

Analysis of factors influencing the intravertebral shell phenomenon after posterior reduction internal fixation of thoracolumbar fracture: a retrospective study.

STUDY DESIGN: A retrospective study. PURPOSE: The study objectives were as follows: 1) to analyze the factors influencing the occurrence of the intravertebral shell phenomenon (ISP) after thoracolumbar spinal fracture surgery and the evolutionary outcome of this phenomenon; and 2) to make recommendations for the clinical prevention and treatment of ISP. METHODS: We retrospectively analyzed 331 patients with single-segment fractures of the thoracolumbar spine treated with internal fixation via a pedicle screw-rod system. Univariate and multivariate logistic regression were used to analyze factors influencing ISP. RESULTS: A total of 260 patients (78.5%) developed ISP after surgery. Reduced bone mineral density, screw insertion depth, degree of vertebral body injury, and excessive vertebral body spreading were significantly associated with the occurrence of ISP (P < 0.05). A total of 166 of the 260 patients were reviewed via CT at 1 year postoperatively. Among them, 104 patients (62.6%) showed shrinkage or healed vertebral cavities, and 62 patients (37.4%) showed enlarged vertebral cavities or collapsed endplates. CONCLUSION: In clinical management, surgeons need to focus on risk factors for ISP, which include decreased bone density, preoperative vertebral overcompression, intraoperative vertebral overextension, screw insertion depth, and the degree of vertebral repositioning. At the 1-year postoperative follow-up, some of the vertebrae with ISP failed to heal or even showed vertebral cleft enlargement, which would affect the stability of the internal fracture fixation device and the quality of the patient's daily life.