Vitamin D, vitamin D supplementation and atrial fibrillation risk in the general population: updated systematic review and meta-analysis of prospective studies

BackgroundSince the association of vitamin D with atrial fibrillation (AF) risk is still unclear, we conducted this updated meta-analysis of prospective studies to identify the relationship between vitamin D or vitamin D supplementation and AF in the general population.MethodsWe conducted a comprehensive search of multiple databases up to May 2023 for studies reporting vitamin D and AF. The hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled by a random-effects model.ResultsA total of seven studies were included in this meta-analysis. Vitamin D deficiency (<20 ng/ml) was associated with increased AF incidence (HR: 1.12, 95% CI: 1.005–1.25). The HR was not significant with vitamin D insufficiency (20–30 ng/ml; HR: 1.09, 95% CI: 0.98–1.21). Each 10 ng/ml increase in serum vitamin D was associated with a significantly decreased AF incidence (HR: 0.95, 95% CI: 0.93–0.97). Two studies reported the effect of vitamin D supplements on AF incidence but reached inconsistent results.ConclusionsVitamin D deficiency or insufficiency was associated with an increased risk of AF in the general population. The role of vitamin D supplementation in AF prevention needs further investigation

Intrinsic Cerebro-Cerebellar Functional Connectivity Reveals the Function of Cerebellum VI in Reading-Related Skills

Funding This work was supported by grants from the National Natural Science Foundation of China (NSFC: 31971036, 31971039, and 31571158).Peer reviewedPublisher PD

Effects of Astragalus Polysaccharides on Associated Immune Cells and Cytokines in Immunosuppressive Dogs

AbstractThe aim of this study was to determine the effects of Astragalus Polysaccharide (APS) on associated Immunity Cells and Cytokines in the immunosuppressive dogs and its dose-effect correlation. One hundred two-month-old male Chinese Countryside Dogs were randomly assigned to five groups: Control group (CG), immunosuppressive group (IG), APS low dose group (50mg/kg, LDG), APS median dose group (100mg/kg, MDG), and APS high dose group (200mg/kg, HDG), each group with twenty animals. After successfully established the dexamethasone-induced immunosuppressive models, with intravenous administer the CG and IG groups were daily dosed with saline, and the other three groups were daily dosed with APS for 7 days. On day 4 and 11 venous blood samples were collected and analyzed to determine the percentages of peripheral blood ANAE+ T lymphocytes, CD4+, CD8+ cells and CD4+/CD8+ ratio; the phagocytic index and percentage of the peritoneal macrophages; and the contents of INF-γ and IL-2. After 7 days administration, the measured parameters as described above in three treated groups increased significantly (P<0.05). Our findings show that the dosage of 200mg/kg APS can significantly enhance the cellular immune level of the immunosuppressive dogs. This study has provided evidence and basis for Astragalus polysaccharides development as companion animal health products as well as for its clinical application

Can annual land use plan control and regulate construction land growth in China?

Annual land use plan (ALUP) stands for the quota allocation of land converted to non-agricultural use, which has been in place since 1987 in China. Although the ALUP has been implemented for more than 30 years and has played an important role in China’s non-agricultural land growth management, little has been done to assess the effect of its implementation. The purpose of this research is to evaluate the effect of the ALUP on controlling the growth of construction land in China. The province-level data on land use in China during the period of 2006–2013 were collected and then analyzed using panel data model. The results show that (1) the ALUP can effectively curb construction land growth, and the construction land decreased about 1721 ha with a 1% increment of the intensity of growth management. Construction land growth is closely related to the implementation intensity of the ALUP, which decreases 30,892 ha under strict implementation but increases an extra 181,451 ha with relaxed implementation; (2) the implementation effect of the ALUP shows significant differences between provinces, and the provinces of northwestern and eastern China show better performance than provinces from the southwest and central regions. National development strategy and region’s differentiation land policy may have contributed to this phenomenon; (3) taking both the goal achievement and effectiveness into account, the implementation of the ALUP is described as effective though not completely successful; and (4) for more efficiency and success, the study proposes some suggestions on improving policy implementation in the future

Windbreak shelter and physiological responses of corn

Windbreaks have been used extensively to improve crop growing conditions and to enhance crop growth and yield. The effectiveness of a windbreak is represented by the amount of windspeed reduction in the sheltered zone and determines the amount of potential benefit the protected crop will receive. The objectives of the research described in this dissertation were to evaluate the various approaches used to assess windbreak effectiveness in terms of windspeed reduction and crop response to shelter-induced environment. The study was conducted at the University of Nebraska-Lincoln Agricultural Research and Development Center near Mead, Nebraska from 1990 to 1992. Windbreak structure, windspeed reductions, air and soil temperatures, humidity, and soil moisture were monitored. Leaf light and CO\sb2 responses; leaf photosynthesis, stomatal conductance, transpiration; and biomass and grain accumulation of corn were measured at various stages of development. Windspeed reduction in shelter was a function of exposed windspeed, windbreak porosity and distance away from the windbreak. When exposed windspeed was below a threshold windspeed, relative windspeed reduction in shelter decreased as the windspeed increased; when windspeed was above the threshold windspeed, relative windspeed reduction was independent of exposed windspeed. The effectiveness of a windbreak also depends on the sensitivity of objects with objects defined as anything needing wind protection. A model was developed to evaluate this effectiveness by considering the critical windspeed for various objects that causes initial damage to the objects. The model was evaluated using measured windspeeds and published data. Leaf light responses were not significantly influenced by windbreaks. Both short term and longer term comparisons suggested that windbreaks did not significantly change chamber-measured leaf photosynthesis, stomatal conductance, transpiration, or water use efficiency. Leaf area, leaf area estimation, and vertical area distribution were not significantly changed by windbreak shelter. Plant biomass and grain accumulation were simulated by a mechanistic model based on radiation use efficiency. The comparison between measured and predicted values for biomass and grain yield showed a good agreement. Windbreaks slightly increased biomass and grain production of corn

Numerical Investigation of Periodic Fluctuations in Energy Efficiency in Centrifugal Pumps at Different Working Points

In order to simulate the energy efficiency fluctuation behavior of an industrial centrifugal pump with a six-blade impeller, a full-scale three-dimensional (3D) an unsteady state computational fluid dynamics (CFD) model was used. Five operational points with different flow fluxes were numerically investigated by using the Navier–Stokes code with shear-stress transport (SST) k-ω turbulence model. The predicted performance curves agreed well with the test data. A sine function was fitted to the transient calculation results and the results show that the efficiency fluctuates mainly on the blade passing frequency, while the fluctuation level varies with flow rate. Furthermore, high efficiency is not necessarily associated with low fluctuation level. The efficiency fluctuation level is high at part-load points, and becomes relatively low when flow rate exceeds the design value. The effect of change in torque is greater than that of the head lift with respect to fluctuations of efficiency. Based upon the analysis of velocity vector distribution of different impeller phase positions, a hypothesis which considers both the effect of pump’s structural shape and flow fluxes was proposed to explain the above behavior by analyzing the impeller–tongue interaction. This work enriches the theoretical system of flow parameters fluctuation of centrifugal pump, and provides useful insight for the optimal design of centrifugal pumps