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Background: This study aimed to investigate the incidence, topographical distribution, morphology, and interrelationship of the metopism and Wormian bones (WBs) in dry adult-Chinese skulls. Materials and methods: In this study, 285 dried adult-Chinese skull specimens from the Department of Anatomy at the Southern Medical University were examined. The incidence of different types of metopism and WBs were recorded. The length of the metopic suture was measured using a flexible ruler. Additionally, the lengths and widths of the WBs were measured using a vernier calliper. Results: The incidence of metopism and WBs in Chinese adults were estimated at 10.18% (29/285) and 63.86% (182/285), respectively. The metopism always accompanied WBs (26/29, 89.66%), but the WBs did not necessarily accompany metopism (26/182, 14.29%). The locations of the WBs in the order of decreasing incidence were the lambdoid suture (78.57%, 143/182), pterion (34.62%, 63/182), asterion (12.09%, 22/182), lambda (8.24%, 15/182), sagittal suture (4.95%, 9/182), and Inca bone (3.85%, 7/182). These locations differed in topographical distribution and morphological patterns. Conclusions: Chinese adults differ in incidence of metopism and WBs from adults of other races, indicating racial differences. The characteristics of WBs vary depending on the cranial site of occurrence. The metopism always accompanies WBs, but the WBs do not necessarily accompany metopism. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The present study aimed to investigate the impact of two Nrf2 agonists, tBHQ and 4-Octyl Itaconate, on nucleus pulposus (NP) degeneration and explore the underlying mechanism. PATIENTS AND METHODS: We isolated the NP cells from the disc tissue of disc herniation patients. NP cells were pretreated with an adequate dose of tBHQ, Itaconate, or the mixture of them, and then subjected to the Lipopolysaccharides (LPS) stimulation to induce degeneration. Besides, the Nrf2 gene silenced NP cells were also used as a comparison. Moreover, the LPS-treated NP cells were also cultured in the mix of tBHQ and Itaconate to determine whether the agonists affected reverse degeneration. RESULTS: LPS treatment suppressed Nrf2 expression and induced the NP cell degeneration with a decrease of cell viability and collagen II expression, an increase of reactive oxygen species (ROS) production, inflammatory cytokine accumulation (IL-1ß, TNF-a), and apoptosis (Caspase3, Caspase8). However, tBHQ or Itaconate pretreated NP cells contained a higher level of Nrf2 protein and alleviated the negative effect caused by LPS, which was abolished with the silencing of Nrf2. Additionally, tBHQ showed a better ability to suppress ROS than Itaconate. Meanwhile, Itaconate inhibited a higher amount of IL-1ß and TNF-a than tBHQ. Interestingly, when NP cells were pretreated with both tBHQ and Itaconate, the result indicated an excellent anti-ROS and anti-inflammatory peculiarity. Furthermore, when NP cells suffered from LPS first and then treated with the agonist, the anti-ROS and anti-inflammatory effects remained. However, the cell viability, collagen II, and apoptotic degree were not improved. CONCLUSIONS: Both tBHQ and Itaconate effectively prevent NP cells from degeneration through anti-ROS and anti-inflammation, and the combined use of them may have better effects. But in comparison, their impact on reversing NP cell degeneration has yet to be proven. [ABSTRACT FROM AUTHOR]

In this paper, the effects of the magnetic coupling of nonadjacent resonators on the optimal frequency of wireless power transfer are addressed. A power analysis has been carried out to identify the adjacent and nonadjacent power flow components. It is found that such cross-coupling effects of nonadjacent resonators would cause the maximum efficiency operation to slightly shift away from the resonance frequency of the resonators. Theoretical reasons for such phenomena are provided and experimentally confirmed with practical measurements in a wireless power transfer system comprising several magnetically coupled resonators arranged in a straight domino form. [ABSTRACT FROM AUTHOR]

Synchronous rectification has previously been adopted in switched-mode circuits for reducing the conduction losses particularly in high-frequency, low-voltage, and high-current applications. This paper presents a generalized “self-driven” ac–dc synchronous rectification technique that can be used even at mains frequency to develop an ac–dc synchronous rectifier that behaves like a diode bridge but with much reduced conduction losses and without control integrated circuits. This generalized concept can be extended from single-phase to multiphase systems. Experiments based on 1- and 2-kW single-phase systems have been successfully conducted for capacitive, inductive, and resistive loads. Very significant power loss reduction (over 50%) has been achieved in the rectification stage at both 110- and 220-V ac mains operations. This patent-pending circuit can be regarded as a direct replacement of a general-purpose diode rectifier. Due to the reduction of power loss, further reduction in the size and cost of the heat sink or thermal management for the power circuit becomes possible. [ABSTRACT FROM AUTHOR]

The planar contactless battery charging system is an emerging technology that can be applied to a wide range of portable consumer electronic products. Beginning with a brief historical background, this paper presents a new single-layer winding array and receiver coil structure with cylindrical ferrite cores for planar contactless battery charging systems. Complying with the “Qi” standard, this design enables multiple devices to be placed and charged simultaneously on the wireless charging pad in a free-positioning manner. The charging flux is totally localized within the covered area between the selected primary winding and the secondary winding inside the load. The electromagnetic characteristics of such winding design are studied in finite-element analysis and confirmed by practical implementation. [ABSTRACT FROM AUTHOR]