Research on Orbital Angular Momentum Recognition Technology Based on a Convolutional Neural Network.

In underwater wireless optical communication (UWOC), a vortex beam carrying orbital angular momentum has a spatial spiral phase distribution, which provides spatial freedom for UWOC and, as a new information modulation dimension resource, it can greatly improve channel capacity and spectral efficiency. In a case of the disturbance of a vortex beam by ocean turbulence, where a Laguerre-Gaussian (LG) beam carrying orbital angular momentum (OAM) is damaged by turbulence and distortion, which affects OAM pattern recognition, and the phase feature of the phase map not only has spiral wavefront but also phase singularity feature, the convolutional neural network (CNN) model can effectively extract the information of the distorted OAM phase map to realize the recognition of dual-mode OAM and single-mode OAM. The phase map of the Laguerre-Gaussian beam passing through ocean turbulence was used as a dataset to simulate and analyze the OAM recognition effect during turbulence caused by different temperature ratios and salinity. The results showed that, during strong turbulence Cn2=1.0×10-13K2m-2/3, when different ω = -1.75, the recognition rate of dual-mode OAM (ℓ = ±1~±5, ±1~±6, ±1~±7, ±1~±8, ±1~±9, ±1~±10) had higher recognition rates of 100%, 100%, 100%, 100%, 98.89%, and 98.67% and single-mode OAM (ℓ = 1~5, 1~6, 1~7, 1~8, 1~9, 1~10) had higher recognition rates of 93.33%, 92.77%, 92.33%, 90%, 87.78%, and 84%, respectively. With the increase in ω, the recognition accuracy of the CNN model will gradually decrease, and in a fixed case, the dual-mode OAM has stronger anti-interference ability than single-mode OAM. These results may provide a reference for optical communication technologies that implement high-capacity OAM.

Neuroprotective effects of metformin on cerebral ischemia-reperfusion injury by regulating PI3K/Akt pathway.

Metformin (Met) is a commonly used drug in the treatment of type 2 diabetes. Currently, it has been found that Met can effectively reduce the incidence of stroke and exert anti-inflammatory effects. However, its role in ischemia-reperfusion (I/R)-induced nerve injury remains unclear. This study aims to investigate the neuroprotective effects of Met in I/R-induced neuron injury as well as the underlying mechanism. A middle cerebral artery occlusion (MCAO) model was established in Sprague Dawley (SD) rats, which were then treated with different doses of Met. Neurological deficits of rats were measured at different times post-surgery. TTC staining was done to observe the volume of cerebral infarction. HE staining was performed to observe pathological changes of brain tissues. Immunohistochemistry was performed to observe the expression of inflammatory factors in the cerebral tissues. qRT-PCR method was used to detect the relative expression of PI3K, Akt mRNA in cells after 24 h of drug action. Western blot method was used to detect the expression of PI3K, p-PI3K, Akt, and p-Akt in hippocampus. What is more, in vitro experiments were performed on BV2 microglia to verify the role of Met against oxygen-glucose deprivation (OGD). As a result, Met dose-dependently attenuated neurological deficits and neuronal apoptosis. Besides, Met administration also significantly reduced BV2 cells apoptosis and inflammatory response. Mechanistically, Met inactivated PI3K/Akt pathway induced by I/R and OGD, while it upregulated PI3K. In conclusion, Met protected rats from cerebral I/R injury via reducing neuronal apoptosis and microglial inflammation through PI3K/Akt pathway.

Moxibustion for Patients with Primary Dysmenorrhea at Different Intervention Time Points: A Randomized Controlled Trial.

PURPOSE: To investigate the effectiveness of moxibustion at different times of the menstrual cycle for patients with primary dysmenorrhea (PD). PATIENTS AND METHODS: Participants were 208 patients allocated to three controlled groups: one pre-menstrual treatment group (Group A), one menstrual-onset treatment group (Group B), and one waiting-list group (Group C). Groups A and B received the same intervention of moxibustion on points SP6 and RN4 but at different times. Group C, the waiting-list group, received no treatment throughout the study. Cox Menstrual Symptom Scale (CMSS) score was the primary outcome. Secondary outcomes were visual analog scale (VAS) score of pain intensity, self-rating anxiety scale (SAS) score, and self-rating depression scale (SDS) score. CMSS and VAS scores were obtained at the baseline stage (three cycles), treatment stage (three cycles), and follow-up stage (three cycles), a total of seven evaluations. SAS and SDS scores were obtained on the day of group allocation and the first day of the follow-up stage, a total of two evaluations. RESULTS: Baseline characteristics were comparable across the three groups. Pain duration (CMSS score) was significantly higher in Group C than in the other two groups at each evaluation (P<0.001). There was also a significant difference in the improvement in pain duration between Group B and Group C (P<0.001) throughout the trial. There were no significant changes in pain severity (CMSS score) after the 3-month treatment in Group A and Group B (P>0.05). Secondary outcomes showed that pre-menstrual moxibustion (Group A) was as effective as menstrual-onset moxibustion (Group B) in relieving pain intensity (VAS score) and negative mood (SDS and SAS scores). CONCLUSION: Moxibustion appears as an effective treatment for PD. Pre-menstrual application is more effective than menstrual-onset application. TRIAL REGISTRATION CHICTRORGCN IDENTIFIER: ChiCTR-TRC-14004627.

Cardiac MR segmentation based on sequence propagation by deep learning.

Accurate segmentation of myocardial in cardiac MRI (magnetic resonance image) is key to effective rapid diagnosis and quantitative pathology analysis. However, a low-quality CMR (cardiac magnetic resonance) image with a large amount of noise makes it extremely difficult to accurately and quickly manually segment the myocardial. In this paper, we propose a method for CMR segmentation based on U-Net and combined with image sequence information. The method can effectively segment from the top slice to the bottom slice of the CMR. During training, each input slice depends on the slice below it. In other words, the predicted segmentation result depends on the existing segmentation label of the previous slice. 3D sequence information is fully utilized. Our method was validated on the ACDC dataset, which included CMR images of 100 patients (1700 2D MRI). Experimental results show that our method can segment the myocardial quickly and efficiently and is better than the current state-of-the-art methods. When evaluating 340 CMR image, our model yielded an average dice score of 85.02 ± 0.15, which is much higher than the existing classical segmentation method(Unet, Dice score = 0.78 ± 0.3).

Involvement of Shh/Gli1 signaling in the permeability of blood-spinal cord barrier and locomotion recovery after spinal cord contusion.

Shh/Gli1 signaling plays important roles in development of spinal cord. How it is involved in spinal cord injury (SCI) remains unclear. In this study, we explored the roles of Shh/Gli1 signaling in SCI by using Shh signaling reporter Gli1lz mice and Gli1 mutant Gli1lz/lz mice. For detecting the Shh/Gli1 signaling after SCI, X-gal staining and double-immunostaining of Shh/PDGFR-ß, Shh/GFAP and LacZ/GFAP was conducted at 3 days post injury (dpi) on Gli1lz mice. To investigate the effects of Gli1 mutation on pathological changes after SCI, astrocytic proliferation and the content of intra-parenchymal Evans Blue were evaluated at 7dpi in wild-type and Gli1lz/lz mice. Furthermore, locomotor recovery was assessed by BMS scoring at 1, 3, 5 and 7dpi. The results of X-gal staining and immunohistochemistry showed that Shh/Gli1 signaling was mainly activated in reactive astrocytes after SCI. The 5-bromo-2-deoxyuridine (BrdU) incorporation assay showed that mutation of Gli1 did not affect the proliferation of astrocytes. However, the leakage of Evans Blue was significantly increased in the injured cord of Gli1lz/lz mice compared to wild-type mice. In addition, locomotor recovery was significantly impaired in the Gli1lz/lz mice. The findings demonstrated that Shh/Gli1 signaling could be induced in reactive astrocytes by SCI, and plays important role in permeability of blood-spinal cord barrier (BSCB) and locomotor recovery after SCI.

Wnt-activated olfactory ensheathing cells stimulate neural stem cell proliferation and neuronal differentiation.

Olfactory ensheathing cells (OECs) are special glial cells localized in olfactory system which secrete large number of neurotrophic factors and promote the migration and survival of neurons. Canonical Wnt/ß-catenin signaling is activated in OECs during development and facilitates the growth and regeneration of axons. In the present study, we investigated the effects of Wnt-activated OECs on the proliferation and differentiation of neural stem cells (NSCs) in vitro. Primary neonatal mouse OECs were cultured and identified by immunostaining of P75 and GFAP. Wnt activation was achieved by lentivirus transfection of dominant-active-ß-catenin (EbC) and examined by immunostaining of PY489. The conditioned medium (CM) of Wnt-activated OECs (wOECs-CM) and control OECs (cOECs-CM) was used to stimulate NSCs. In proliferation assay, wOECs-CM could increase the percentage of Ki67/Sox2 double positive cells. Under differentiation condition, wOECs-CM could maintain the expression of Nestin and promote the differentiation of NSCs into Tuj1-positive neurons. Taken together, our data revealed that wOECs stimulates the proliferation and differentiation of NSCs in a secretory manner, indicating that combined transplantation of wOECs and NSCs may be beneficial for regeneration.

Investigation of 3 dB Optical Intensity Spot Radius of Laser Beam under Scattering Underwater Channel.

An important step in the design of receiver aperture and optimal spacing of the diversity scheme for an underwater laser communication system is to accurately characterize the two-dimensional (2D) spatial distribution of laser beam intensity. In this paper, the 2D optical intensity distribution and 3 dB optical intensity spot radius (OISR) are investigated due to the dominating optical intensity of laser beam being within the 3 dB OISR. By utilizing the Henyey-Greenstein function to compute the scattering angles of photons, the effects of the scattering underwater optical channel and optical system parameters on 3 dB OISR are examined based on the Monte Carlo simulation method. We have shown for the first time that in the channel with a high density of scattering particles, the divergence angle of the laser source plays a negligible role in 3 dB OISR. This is an interesting phenomenon and important for optical communication as this clearly shows that the geometric loss is no longer important for the design of receiver aperture and optimal spacing of the diversity scheme for the underwater laser communication system in the highly scattering channel.

Acupoint herbal plaster for patients with primary dysmenorrhea: study protocol for a randomized controlled trial.

BACKGROUND: Primary dysmenorrhea (PD), is one of main gynecological complaints in women of child-bearing age. Common medications for PD do not always achieve satisfactory outcome of pain relief. Hence, both health professionals and patients are seeking help from complementary and alternative medicine. The acupoint herbal plaster (AHP), which appears to be a safe and effective way to alleviate menstrual pain, as well as to improve other PD-related symptoms. Despite similar clinical studies for this condition in the past, no high-quality methodology-based clinical trial has been reported to date. The current study aims to assess the efficacy of the AHP compared with the acupoint placebo plaster (APP) and being placed on a waiting-list control group in patients with primary dysmenorrhea. METHODS/DESIGN: This study is a randomized, single-center, placebo-controlled clinical trial. A total of 180 women with PD will be included and randomly allocated to the AHP, APP and waiting-list (WL) groups in a 1:1:1 ratio. Patients in the AHP group will be provided with herbal plasters (Shaofuzhuyu decoction) on various acupoints: Shenque (CV8), Guanyuan (CV4), Qihai (CV5), Ciliao (BL32) and Zigong (EX-CA1). Women in the APP group will receive placebo plasters on the same acupoints, and no intervention will be given to the WL group until completion of the study. The primary outcome will be pain intensity reduction measured by a Visual Analog Scale (VAS), with other outcome measurements including the Cox Menstrual Symptom Scale (CMSS), the 12-Item Short Form Health Survey (SF-12) and the Participant Global Impression of Change (PGIC). All assessments will be performed at baseline, each menstrual cycle during the treatment course and the follow-up course. Any adverse events will be recorded throughout the study. DISCUSSION: This is the first study to compare the changes in menstrual pain after three different interventions: the active intervention (AHP), the placebo intervention (APP), and a period of no intervention (WL). This three-arm randomized controlled trial (RCT) aims to investigate the relative contributions of the specific (AHP vs. APP) and non-specific (APP vs. WL) effects to the overall clinical effects of the active AHP on women with PDM. The scientific and rigorous methodology design of this trial should gather good evidence to assess the curative effects and safety of the AHP on PD. Moreover, the results of this study may provide evidence-based references for the treatment of menstrual pain in future. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ID: ChiCTR-TRC-16008701. Registered on 22 July 2016.

[Current situation of acupuncture in New Zealand].

The beginning of TCM acupuncture in New Zealand dates back to the middle of 19th century. After self-improvement for more than 100 years, TCM acupuncture has gained a considerable development. From the perspective of history and current situation, the development of acupuncture in New Zealand was elaborated in this article; in addition, the sustainable development of acupuncture was discussed from the perspective of education and training. In New Zealand, the TCM acupuncture and dry needling have played a dominant role in acupuncture treatments, which are practiced by TCM practitioners and physical therapists. The TCM acupuncture is widely applied in department of internal medicine, surgery, gynecology, and pediatrics, etc., while the dry needling is li-mited for traumatology and pain disorder. Therefore, including TCM acupuncture into the public medical and educational system in New Zealand should be an essential policy of Ministry of Health to provide welfare for the people.

Influence of fluoride and chloride on corrosion behavior of NiTi orthodontic wires.

The influence of fluoride and chloride ions on the corrosion behavior of nearly equiatomic nickel-titanium orthodontic wires was studied using conventional electrochemical measurement methods, including corrosion potential, potentiodynamic and cyclic potentiodynamic polarization measurements. In addition, scanning electron microscopy was employed to observe the surface morphology before and after the test. All the electrochemical parameters are analyzed based on the sample standard deviations. The results indicated that NiTi alloy is primarily susceptible to localized corrosion when exposed to a solution containing chloride, while it is susceptible to general corrosion when subjected to a solution containing fluoride. Furthermore, the synergistic interaction of fluoride and chloride on corrosion of NiTi alloy is associated with their respective molar concentrations.