3,646 research outputs found
Periodic Radio Variability in NRAO 530: Phase Dispersion Minimization Analysis
In this paper, a periodicity analysis of the radio light curves of the blazar
NRAO 530 at 14.5, 8.0, and 4.8 GHz is presented employing an improved Phase
Dispersion Minimization (PDM) technique. The result, which shows two persistent
periodic components of and years at all three frequencies,
is consistent with the results obtained with the Lomb-Scargle periodogram and
weighted wavelet Z-transform algorithms. The reliability of the derived
periodicities is confirmed by the Monte Carlo numerical simulations which show
a high statistical confidence. (Quasi-)Periodic fluctuations of the radio
luminosity of NRAO 530 might be associated with the oscillations of the
accretion disk triggered by hydrodynamic instabilities of the accreted flow.
\keywords{methods: statistical -- galaxies: active -- galaxies: quasar:
individual: NRAO 530}Comment: 8 pages, 5 figures, accepted by RA
Health First: The Sustainable Development of Physical Education in Chinese Schools
Strengthening school physical education (PE) is of great strategic significance in enhancing students’ all-round development, which mainly includes their morality, intelligence and physique development. School PE has upheld the guiding ideology of ‘health first’ and continuously enhanced PE development in China. The guiding ideology of ‘health first’ has involved three stages: (1) improving students’ physical conditions; (2) enhancing students’ physical health, mental health and ability to socially adapt; and (3) promoting students’ all-round human development. This paper provides a comprehensive review of the social and political contexts, aims, policies and practice of Chinese school PE, and goes on to analyze different sports views that reshape the value orientation of ‘health first’. Moreover, this paper shows that a regulated and institutionalized Chinese school PE system has gradually formed with the evolving ideology of ‘health first’ and policy changes, but it has a long way to accomplish the new mission of ‘foster virtue through education’ in students’ all-round development. For students’ all-round development, Chinese school PE needs to prioritize the value proposition of ‘foster virtue through education’, advance the theoretical research on PE curriculum and teaching materials, and further enhance the reform of the assessment and evaluation system of constitutional health. Eventually, a new national school PE core curriculum needs to be established to integrate the mission of ‘foster virtue through education’ and guiding ideology of ‘health first’ together
Health First: The Sustainable Development of Physical Education in Chinese Schools
Strengthening school physical education (PE) is of great strategic significance in enhancing students’ all-round development, which mainly includes their morality, intelligence and physique development. School PE has upheld the guiding ideology of ‘health first’ and continuously enhanced PE development in China. The guiding ideology of ‘health first’ has involved three stages: (1) improving students’ physical conditions; (2) enhancing students’ physical health, mental health and ability to socially adapt; and (3) promoting students’ all-round human development. This paper provides a comprehensive review of the social and political contexts, aims, policies and practice of Chinese school PE, and goes on to analyze different sports views that reshape the value orientation of ‘health first’. Moreover, this paper shows that a regulated and institutionalized Chinese school PE system has gradually formed with the evolving ideology of ‘health first’ and policy changes, but it has a long way to accomplish the new mission of ‘foster virtue through education’ in students’ all-round development. For students’ all-round development, Chinese school PE needs to prioritize the value proposition of ‘foster virtue through education’, advance the theoretical research on PE curriculum and teaching materials, and further enhance the reform of the assessment and evaluation system of constitutional health. Eventually, a new national school PE core curriculum needs to be established to integrate the mission of ‘foster virtue through education’ and guiding ideology of ‘health first’ together
Population Genetics of Two Asexually and Sexually Reproducing Psocids Species Inferred by the Analysis of Mitochondrial and Nuclear DNA Sequences
Background: The psocids Liposcelis bostrychophila and L. entomophila (Psocoptera: Liposcelididae) are found throughout the world and are often associated with humans, food stores and habitations. These insects have developed high levels of resistance to various insecticides in grain storage systems. However, the population genetic structure and gene flow of psocids has not been well categorized, which is helpful to plan appropriate strategies for the control of these pests. Methodology/Principal Findings: The two species were sampled from 15 localities in China and analyzed for polymorphisms at the mitochondrial DNA (Cytb) and ITS (ITS1-5.8S-ITS2) regions. In total, 177 individual L. bostrychophila and 272 individual L. entomophila were analysed. Both Cytb and ITS sequences showed high genetic diversity for the two species with haplotype diversities ranged from 0.15460.126 to 1.00060.045, and significant population differentiation (mean FST = 0.358 for L. bostrychophila; mean FST = 0.336 for L. entomophila) was also detected among populations investigated. A Mantel test indicated that for both species there was no evidence for isolation-by-distance (IBD). The neutrality test and mismatch distribution statistics revealed that the two species might have undergone population expansions in the past. Conclusion: Both L. bostrychophila and L. entomophila displayed high genetic diversity and widespread population genetic differentiation within and between populations. The significant population differentiation detected for both psocids may b
Withaferin A promotes proliferation and migration of brain endothelial cells
Purpose: To investigate the effect of withaferin A (WFA) on the proliferation and migration of brain endothelial cells.Methods: BALB-5023 mouse microvascular cells were treated with a range of withaferin A (WFA) concentrations from 10 to 100 ng/mL. Dojindo’s CCK-8 cell proliferation kit was used for the analysis of cell proliferation. Transwell cell culture inserts were used to determine the migration potential of WFAtreated endothelial cells. Absorbance was measured at 450 nm on an enzyme-linked immunosorbent(ELISA) reader.Results: The results revealed a significant increase in the proliferation and migration of endothelial cells following treatment with a low concentration (30 ng/mL) of WFA compared with the higher concentration (> 10 ng/mL). The effect was further enhanced when WFA was used in combination with soluble Fas ligand (sFasL). Autocrine signaling of vascular endothelial growth factor (VEGF) by endothelial cellswas significantly increased following treatment with WFA or in combination with sFasL. WFA increased the expression of Fas on endothelial cells, suggesting the involvement of sFasL in the proliferation and migration of brain endothelial cells.Conclusion: Thus, WFA promotes the proliferation and migration of endothelial cells through increase in the expression of Fas and secretion of VEGF.Keywords: Endothelial cells, Vascular endothelial growth factor, Microvascular, Vascular disease, Withaferin
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