A bidirectional push–pull/H‐bridge DC/DC converter for a low‐voltage energy storage system is proposed in this paper. It comprises the push–pull converter, the phase‐shifted H‐bridge converter, and ...the transformer. The push–pull converter is connected to the low‐voltage side, and it is controlled by 0.5 fixed duty ratio. The phase‐shifted H‐bridge converter is connected to the high‐voltage side, and it is controlled by an extended phase shift scheme with zero voltage switching (ZVS). Compared with the conventional dual active bridge (DAB) DC/DC converter, the proposed converter has a simple structure—there are only two power switches with a common ground and simple gate‐driving circuits in the low‐voltage side. The 600‐W laboratory prototype was developed to confirm the theoretical analysis and the validity of the proposed converter.
A bidirectional push–pull/H‐bridge DC/DC converter for a low‐voltage energy storage system is proposed in this paper. It comprises the push–pull converter, the phase‐shifted H‐bridge converter, and the transformer.
The traditional understanding of craniocervical alignment emphasizes specific anatomical landmarks. However, recent research has challenged the reliance on forward head posture as the primary ...diagnostic criterion for neck pain. An advanced relationship exists between neck pain and craniocervical alignment, which requires a deeper exploration of diverse postures and movement patterns using advanced techniques, such as clustering analysis. We aimed to explore the complex relationship between craniocervical alignment, and neck pain and to categorize alignment patterns in individuals with nonspecific neck pain using the K-means algorithm.
This study included 229 office workers with nonspecific neck pain who applied unsupervised machine learning techniques. The craniocervical angles (CCA) during rest, protraction, and retraction were measured using two-dimensional video analysis, and neck pain severity was assessed using the Northwick Park Neck Pain Questionnaire (NPQ). CCA during sitting upright in a comfortable position was assessed to evaluate the resting CCA. The average of midpoints between repeated protraction and retraction measures was considered as the midpoint CCA. The K-means algorithm helped categorize participants into alignment clusters based on age, sex and CCA data.
We found no significant correlation between NPQ scores and CCA data, challenging the traditional understanding of neck pain and alignment. We observed a significant difference in age (F = 140.14, p < 0.001), NPQ total score (F = 115.83, p < 0.001), resting CCA (F = 79.22, p < 0.001), CCA during protraction (F = 33.98, p < 0.001), CCA during retraction (F = 40.40, p < 0.001), and midpoint CCA (F = 66.92, p < 0.001) among the three clusters and healthy controls. Cluster 1 was characterized by the lowest resting and midpoint CCA, and CCA during pro- and -retraction, indicating a significant forward head posture and a pattern of retraction restriction. Cluster 2, the oldest group, showed CCA measurements similar to healthy controls, yet reported the highest NPQ scores. Cluster 3 exhibited the highest CCA during protraction and retraction, suggesting a limitation in protraction movement.
Analyzing 229 office workers, three distinct alignment patterns were identified, each with unique postural characteristics; therefore, treatments addressing posture should be individualized and not generalized across the population.
In this study, a three-dimensional compact antenna solution for the automotive industry is proposed. The antenna solution is designed to fit in a shark-fin case and is easily fabricated from a ...printed circuit board and a metal sheet with low-cost process and materials. The antenna solution covers Long Term Evolution (LTE), GPS, WLAN, and Wireless Access in the Vehicular Environment (WAVE) bands (850 MHz, 1575 MHz, 2.4 GHz, and 5.9 GHz, respectively). The planar inverted-F antennas are used as multiple-input-multiple-output antennas for the LTE band due to their low-profile structure. Modified planar monopoles are used to obtain omnidirectional radiation patterns for WLAN and WAVE bands. Antenna characteristics such as return loss, isolation, and radiation pattern have been simulated and measured to confirm the possibility for use in automotive applications.
Novel mesoporous silicas rolled with silica sheets with 2D regular spacing were prepared using a self-assembled graphene oxide (GO) template formed by mixing GO with Pluronic123 (P123). ...Self-assembled GO templated mesoporous silicas (SGT-PMS) showed well-developed X-ray diffraction peaks with d-spacings of 9.8-10.8 nm depending on the amount of GO, indicating mesoporous structures. The specific surface areas increased from 603.8 to 861.2 m
g
on adding GO. The pore size distribution was in the range 5.1-5.8 nm and pore volume in the range 0.80-0.99 m
g
. The SEM images of SGT-PMS showed irregular elliptical particles with various sizes. TEM images showed that the cross section of SGT-PMS particles comprises a roll of silica sheets with 2D regular spacing. The pore walls of SGT-PMS are firmer and thicker than those for PMS without GO as indicated by the corresponding intensities of Q
and Q
signals. These results were explained well by the self-assembled GO templating mechanism.
The lower quarter Y-balance test (YBT-LQ) has been recommended as a measure of dynamic postural control in the clinical setting; however, information about the relationship between performance on the ...YBT-LQ and joint kinematics is limited. Thus, the kinematic predictors responsible for performance on the YBT-LQ need to be identified for accurate evaluation of dynamic postural control.
To identify the kinematic predictors that best explain variance in performance on the YBT-LQ.
Cross-sectional design.
University motion analysis laboratory.
Thirty physically active participants.
All participants performed the YBT-LQ. The kinematics of the trunk and lower extremity at maximal reach in each direction of the YBT-LQ were monitored using a 3-dimensional motion analysis system.
The correlations between reach distance and joint kinematics were assessed using Pearson's correlation coefficient, and the best predictors of performance on the YBT-LQ were determined using a stepwise multiple regression analysis.
Ankle dorsiflexion was the best single predictor of normalized reach in the anterior direction of the YBT-LQ (r(2) = 0.50), and the combination of ankle dorsiflexion and trunk extension explained 65% of the variance in the anterior normalized reach. Hip flexion was the best single predictor of posteromedial (r(2) = 0.60) and posterolateral (r(2) = 0.71) normalized reaches of the YBT-LQ. The combination of hip flexion and ipsilateral trunk bending and the combination of hip flexion and contralateral trunk bending accounted for 69% and 80% of the variance in the posteromedial and posterolateral normalized reaches of the YBT-LQ, respectively.
These findings provide useful information on the relative contribution of joint kinematics to performance on the YBT-LQ when evaluating dynamic postural control.
It is unclear which factors contribute to the developing pressure pain hypersensitivity of the upper trapezius, a type of neurophysiological hyperexcitability. The present study investigated the ...relationship between physical and psychological factors and pressure pain hypersensitivity of the upper trapezius for each sex. In total, 154 individuals with neck/shoulder myofascial pain participated, among 372 food service workers. Participants completed a questionnaire (Beck Depression Inventory, and Borg Rating of Perceived Exertion scale) and were photographed to measure posture. Pressure pain sensitivity, 2 range of motions (cervical lateral bending and rotation), and 4 muscle strengths (serratus anterior, lower trapezius LT, biceps, and glenohumeral external rotator) were measured by a pressure algometer, iPhone application, and handheld dynamometer, respectively. For each sex, forward multivariate logistic regression was used to test our a priori hypothesis among selected variables that a combination of psychosocial and physical factors contributed to the risk for pressure pain hypersensitivity. In multivariate analyses, LT strength (odds ratio = 0.94, 95% confidence interval = 0.91-0.97, P = .001) was the only significant influencing factor for pressure pain hypersensitivity in men. Dominant painful ipsilateral cervical rotation range of motion (odds ratio = 0.96, 95% confidence interval = 0.92-0.99, P = .037) was the only influencing factor for pressure pain hypersensitivity in women. LT strength and dominant painful ipsilateral cervical rotation range of motion could serve as guidelines for preventing and managing pressure pain hypersensitivity of the upper trapezius in food service workers with nonspecific neck/shoulder myofascial pain.
The craniocervical flexion test (CCFT) is commonly used for assessing the performance and function of the deep cervical flexor muscles; however, objective measurements of cervical segmental motion ...during craniocervical flexion (CCF) are lacking. Therefore, the purpose of this study aimed to investigate cervical segmental motions during CCFT and determine the relationship between changes of cervical segmental motions and the cervical lordotic angle. A cross-sectional study of prospectively collected data. Twenty healthy participants without neck pain underwent standing cervical radiography (lateral view) to measure the cervical lordotic angle, followed by radiography in supine position during the CCFT. The occipito-atlantal (OA) joint angle, atlantoaxial (AA) joint angle, and cervical spinous process posterior displacement (CSPPD) of the C1-C6 vertebrae were measured using lateral cervical radiographs taken during the initial (20 mm Hg) and low-stage (24 mm Hg) CCFT conditions. The CCF motion during the low-stage CCFT was characterized by a significantly increased OA joint angle, decreased AA joint angle, and increased C1-C6 CSPPD compared with the initial stage (P < .05). The change in the value of C1-C6 CSPPD at low-stage CCFT showed a significant positive correlation with the cervical lordotic angle. These results indicate that the cervical lordotic angle is important in minimizing CSPPD and performing appropriately-isolated CCF motion during CCFT.
Scope
Alzheimer's disease (AD) is associated with amyloid beta peptide (Aβ25‐35) accumulation in brains, which induces neurotoxicity and cognitive impairment. The effects of Ishige okamurae, an ...edible brown algae, on Aβ25‐35‐induced cognitive impairment and neuronal toxicity is investigated. The aim of this study is to determine the molecular mechanisms responsible for I. okamurae extracts (IOE) mediating anti‐AD effects.
Methods and Results
Oral administration of IOE significantly attenuated Aβ25‐35‐induced cognitive deficits, as estimated by Y‐maze and Morris water maze tests. IOE also attenuated the Aβ25‐35‐induced cellular apoptosis and expression of inducible isoforms of nitric oxide synthases (iNOS) and cyclooxygenase‐2 (COX‐2) in mouse brains and PC12 cells. In addition, Aβ25‐35‐induced phosphorylation of ERK, p38 MAPK, and JNK in mouse brains and PC12 cells is significantly abolished by administration of IOE. In PC12 cells, pretreatment of signal inhibitors (PD98059 (MEK inhibitor), SB203580 (p38 MAPK inhibitor), and SP600125 (JNK inhibitor)) recovers Aβ25‐35‐mediated cellular dysregulations to the same extent as does IOE pretreatment.
Conclusion
Taken together, the data suggest that Aβ25‐35‐induced AD progress may be attenuated by administration of IOE through prevention of Aβ25‐35‐induced phosphorylation of ERK, p38 MAPK, and JNK.
Accumulation of amyloid beta peptide in brain tissue is considered to be a major cause of Alzheimer's disease (AD). Amyloid beta peptide can induce the phosphorylation of MAPKs in the brain, and elevated phosphorylation of MAPKs increase the neuroinflammation and neuronal cell death, resulting in cognitive impairment. This study reveals that oral administration of Ishige okamurae extracts significantly attenuate the amyloid beta peptide mediated AD progress through attenuating the phosphorylation of MAPKs.
Neuroinflammation is one of the critical causes of neuronal loss and cognitive impairment. We aimed to evaluate the anti-neuroinflammatory properties of
using mice intracerebroventricularly injected ...with lipopolysaccharides (LPS) and LPS-treated C6 glioma cells. We found that the short- and long-term memory deficits of LPS-injected mice were improved by oral administration of
extracts (IOE). LPS-induced neuronal loss, increase in amyloid-β plaque, and expression of COX-2 and iNOS were restored by IOE. In addition, LPS-induced activation of Toll-like receptor-4 (TLR-4) and its downstream molecules, such as MyD88, NFκB, and mitogen-activated protein kinases (MAPKs), were significantly attenuated in the brains of mice fed with IOE. We found that pretreatment of IOE to C6 glioma cells ameliorated LPS-induced expression of TLR-4 and its inflammatory cascades, such as MyD88 expression, reactive oxygen species production, MAPKs phosphorylation, and NFκB phosphorylation with consequent downregulation of COX-2, iNOS, proinflammatory cytokines, and nitric oxide expression. Furthermore, IOE (0.2 µg/mL) was found to have equivalent efficacy with 10 μM of MyD88 inhibitor in preventing LPS-induced inflammatory responses in C6 glioma cells. Taken together, these results strongly suggest that IOE could be developed as a promising anti-neuroinflammatory agent which is able to control the TLR-4/MyD88-dependent signaling pathways.
Silicon carbide (SiC) was prepared by carbothermal reduction of a crystalline-layered sodium silicate (δ-Na
2
Si
2
O
5
)/carbon nanocomposite (LCN), which contained a stacked carbon film embedded ...with cobalt between the silicate layers. Subsequent sintering of this mixture for 3 h at 1000-1350°C resulted in the formation of graphitic carbon and SiC. Meanwhile, sintering without a cobalt catalyst resulted in the formation of graphitic carbon, regardless of the temperature. The use of a cobalt catalyst allowed the formation of a pure SiC phase at 1350°C. The formed SiC had an irregular worm-like morphology, with a particle size of ~5 µm. The Brunauer-Emmett-Teller surface areas of graphitic carbon and SiC were 28-150 and ~7.0 m
2
/g, respectively. We concluded that graphite and SiC were produced at this low sintering temperature because of the cobalt catalyst, which facilitated nanomixing of carbon and SiO
2
by sandwiching the carbon films between the silicate layers.
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