86 research outputs found

    Effect of total flavonoids from Drynaria rhizome on bone loss in ovariectomized rats

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    Purpose: To determine the potential effect of total flavonoids from Drynaria rhizome on bone loss in ovariectomized (OVX) rats. Methods: The rats were divided into four groups: normal control, ovariectomized (OVX) control, and two Drynaria rhizome (DR) flavonoids treatments. Post-operation, osteoporotic OVX rats were given Drynaria rhizome total flavonoids for 3 months. Thereafter, the expressions of bone-related genes and biochemical indices were investigated in samples taken from the serum and bone of the rats. Results: Treatment with total flavonoids from Drynaria rhizome prevented bone mineral loss and improved some related biochemical indices associated with osteoporosis: alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP), bone gla protein (BGP) and estradiol (E2). Reverse transcription-polymerase chain reaction (RT-PCR) data showed that treatment with the total flavonoids significantly downregulated mRNA expression of Wnt10b, β-catenin, recombinant human bone morphogenetic protein-2 (BMP2) and BMP4 in OVX rats, but significantly reversed OVX-induced downregulation of dickkopf1 (Dkk1) mRNA expression. Conclusion: These results indicate that total flavonoids from Drynaria rhizome exert anti-osteoporotic effects in rats via WNT signaling and BMP-2 signaling pathways

    Optimization of extraction of total flavonoids from Drynaria rhizome, and its effect on osteoclast differentiation

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    Purpose: To optimize the extraction parameters for total flavonoids of Drynaria rhizome, and determine their effect on osteoclast differentiation and bone resorption in vitro. Methods: A 5-level 3-factor central composite design was applied to the optimization of extract yield of total flavonoids from Drynaria rhizome. Response Surface Methodology (RSM) design was used to optimize total flavonoids extraction from Drynaria rhizome. The independent factors included extraction temperature (A), extraction time (B) and liquid: solid ratio (C). Moreover, NFATc1, DC-STAMP, cathepsin K and MMP-9 mRNA expressions were determined. Results: Values obtained were fitted into a second-order polynomial equation with multiple regression analysis using a statistical method. Analysis of variance results indicate that the independent variables influenced total flavonoid extraction from Drynaria rhizome. The optimal conditions for extraction yield were extraction temperature of 75 oC, extraction time of 100 min, and liquid: solid ratio of 107:1. The yield of 5.38 ± 0.62 % was consistent with these optimized conditions, which was an indication of the accuracy of the model. Experiments revealed that total flavonoids from Drynaria rhizome regulated the expression levels of NFATc1, DC-STAMP, cathepsin K and MMP-9 mRNA Conclusion: This study has successfully optimized the extraction yield of total flavonoids from Drynaria rhizome. The total flavonoids inhibit osteoclast differentiation and bone resorption. Thus, they may be beneficial in the treatment of bone diseases

    Thermal management performances of PCM/water cooling-plate using for lithium-ion battery module based on non-uniform internal heat source

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    In order to improve the working performance of the lithium-ion battery, the battery module with Phase change material/water cooling-plate was designed and numerically analyzed based on the energy conservation and fluid dynamics. The non-uniform internal heat source based on 2D electro-thermal model for battery LiFePO4/C was used to simulate the heat generation of each battery. Then factors such as height of water cooling-plate, space between adjacent batteries, inlet mass flow rate, flow direction, thermal conductivity and melting point of PCM were discussed to research their influences on the cooling performance of module. And the 5 continuous charge-discharge cycles was used to research the effect of PCM/water cooling plate on preventing thermal runaway. The results showed that the water cooling plate set close to the near-electrode area of battery removed the majority of heat generated during discharging and decreased the maximum temperature efficiently. The PCM between the adjacent batteries could improve the uniformity of temperature field. In addition, the PCM/water cooling plate could limit the maximum temperature effectively and improve the uniformity of temperature field during the 5 continuous charge-discharge cycles. As a result, it prevented the emergence of thermal runaway and increased the safety of module. (C) 2017 Elsevier Ltd. All rights reserved

    A Missing Key to Understand the Electrical Resonance and the Mechanical Property of Neurons: a Channel-Membrane Interaction Mechanism

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    The recent study of the interaction between the fatty acyl tails of lipids and the K+ channel establishes the connection between flexoelectricity and the ion channel's dynamics, named Channel-Membrane Interaction (CMI), that may solve the electrical resonance in neurons

    Effect of total flavonoids from Drynaria rhizome on bone loss in ovariectomized rats

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    Purpose: To determine the potential effect of total flavonoids from Drynaria rhizome on bone loss in ovariectomized (OVX) rats. Methods: The rats were divided into four groups: normal control, ovariectomized (OVX) control, and two Drynaria rhizome (DR) flavonoids treatments. Post-operation, osteoporotic OVX rats were given Drynaria rhizome total flavonoids for 3 months. Thereafter, the expressions of bone-related genes and biochemical indices were investigated in samples taken from rat serum and bone. Results: Treatment with total flavonoids from Drynaria rhizome prevented bone mineral loss and improved some related biochemical indices associated with osteoporosis, namely, alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP), bone gla protein (BGP) and estradiol (E2). Reverse transcription-polymerase chain reaction (RT-PCR) data showed that treatment with the total flavonoids significantly downregulated mRNA expression of Wnt10b, β-catenin, recombinant human bone morphogenetic protein-2 (BMP2) and BMP4 in OVX rats, but significantly reversed OVX-induced downregulation of dickkopf1 (Dkk1) mRNA expression. Conclusion: These results indicate that total flavonoids from Drynaria rhizome exert anti-osteoporotic effects in rats through the WNT signaling and BMP-2 signaling pathways

    Investigation of thermal management for lithium-ion pouch battery module based on phase change slurry and mini channel cooling plate

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    In this paper, the thermal management based on phase change slurry (PCS) and mini channel cooling plate for the lithium-ion pouch battery module was proposed. The three-dimensional thermal model was established and the optimum structure of the cooling plate with mini channel was designed with the orthogonal matrix experimental method to balance the cooling performance and energy consumption. The simulation results showed that the cooling performance of PCS consisting of 20% n-octadecane microcapsules and 80% water was better than that of pure water, glycol solution and mineral oil, when the mass flow rate was less than 3 x 10(-4) kg s(-1). For different concentrations of PCS, if the mass flow rate exceeded the critical value, its cooling performance was worse than that of pure water. When the cooling target for battery maximum temperature was higher than 309 K, the PCS cooling with appropriate microcapsule concentration had the edge over in energy consumption compared with water cooling. At last, the dimensionless empirical formula was obtained to predict the effect of the PCS's physical parameters and flow characteristics on the heat transfer and cooling performance. The simulation results will be useful for the design of PCS based battery thermal management systems. (C) 2018 Elsevier Ltd. All rights reserved

    Descriptive and Network Post-Occupancy Evaluation of the Urban Public Space through Social Media: A Case Study of Bryant Park, NY

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    In modern cities, urban public spaces, such as parks, gardens, plazas, and streets, play a big role in people’s social activities, physical activities, mental health, and overall well-being. However, the traditional post-occupancy evaluation (POE) process for public spaces such as large urban parks is extremely difficult, especially for long-term user experiences through observations, surveys, and interviews. On the other hand, social media has emerged as a major media outlet recording millions of user experiences to the public, which provides opportunities to inform how public space is used and perceived by users. Furthermore, unlike previous research that primarily presented descriptive characters of park programs, our study employs a network model to elucidate the interactive relationships and intensities among reported park elements, human activities, and experiences. This approach enables us to track the sources within the space that impact people’s perceptions, such as weather conditions, food options, and notable landmarks. The utilization of this network model opens avenues for future research to comprehensively investigate the factors shaping people’s perceptions in public open spaces. This study uses Bryant Park as an example and presents a new analytical framework, POSE (post-occupancy social media evaluation), to support long-term POE studies for large public spaces. Methods such as data automation, descriptive statistics, and social network analysis were used. The identification and quantification of meaningful park activities, scenes, and sentiments as well as their relationships will help optimize the design and management of park programs

    Bifunktionelle Ni/Zeolith Katalysatoren für die Hydrodeoxygenierung von Mikroalgenöl und Lignin

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    Synergistic effects between proximal metal and acid sites in zeolites have been studied with respect to elementary reactions of biomass conversion. Uniformity of Ni particles is crucial to prevent particle growth during hydrodeoxygenation (HDO). Bifunctional Ni/HZSM-5 at fixed metal loading catalyzes phenol HDO, with a rate increasing in proportion to the Brønsted acid site concentration. Activities of acid site catalyzed dehydration and alkylation of alcohols and phenols not only scale with the concentrations of Brønsted and Lewis acid sites, but also depend on the synergy between them.Synergistische Effekte der räumlichen Nähe von Metall und Säurezentren in Zeolithen wurden in Bezug auf elementare Reaktionen bei der Umsetzung von Biomasse untersucht. Identische Größe von Ni Partikeln ist wichtig um deren Wachstum während der Hydrodeoxygenierung (HDO) zu verhindern. Bei konstanter Metallbeladung katalysiert bifunktioneller Ni/HZSM-5 Phenol HDO mit einer Rate, die proportional zur Brønstedsäure Konzentration ansteigt. Die Aktivitäten der säurekatalysierten Dehydratisierung und Alkylierung von Alkoholen und Phenolen hängen nicht nur von den Konzentrationenen der Brønsted- und Lewis-Säurezentren ab, sondern auch deren Synergie
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