Enhancing Hydrogen Generation Through Nanoconfinement of Sensitizers and Catalysts in a Homogeneous Supramolecular Organic Framework.

Enrichment of molecular photosensitizers and catalysts in a confined nanospace is conducive for photocatalytic reactions due to improved photoexcited electron transfer from photosensitizers to catalysts. Herein, the self-assembly of a highly stable 3D supramolecular organic framework from a rigid bipyridine-derived tetrahedral monomer and cucurbit[8]uril in water, and its efficient and simultaneous intake of both [Ru(bpy)3 ]2+ -based photosensitizers and various polyoxometalates, that can take place at very low loading, are reported. The enrichment substantially increases the apparent concentration of both photosensitizer and catalyst in the interior of the framework, which leads to a recyclable, homogeneous, visible light-driven photocatalytic system with 110-fold increase of the turnover number for the hydrogen evolution reaction

Error-voltage-based open-switch fault diagnosis strategy for matrix converters with model predictive control method

This paper proposes an error-voltage based open-switch fault diagnosis strategy for matrix converter (MC). A finite control set model predictive control (FCS-MPC) method is used to operate the MC. The MC system performances under normal operation and under a single open-switch fault operation are analyzed. A fault diagnosis strategy has also been implemented in two steps. First, the faulty phase is detected and identified based on a comparison of the reference and estimated output line-to-line voltages. Then, the faulty switch is located by considering the switching states of the faulty phase. The proposed fault diagnosis method is able to locate the faulty switch accurately and quickly without additional voltage sensors. Simulation and experimental results are presented to demonstrate the feasibility and effectiveness of the proposed strateg

Synthesized Attributes of Water Use by Regional Vegetation: A Key to Cognition of “Water Pump” Viewpoint

Recently, the frequent seasonal drought in Southwest China has brought considerable concerns and continuous heated arguments on the “water pump” viewpoint (i.e., the water demand from Hevea spp. and Eucalyptus spp. can be treated as a water pump) once again. However, such viewpoint just focused on water consumption from vegetation transpiration and its ecoenvironment impacts, which had not considered other attributes of vegetation, namely, water saving and drought resistance, and hydrological regulation (water conservation) into consideration. Thus, in this paper, the synthesized attributes of regional vegetation water use had been mainly discussed. The results showed that the study on such aspects as the characters of water consumption from vegetation transpiration, the potential of water saving and drought resistance, and the effects of hydrological regulation in Southwest China lagged far behind, let alone the report on synthesized attributes of water utilization with the organic combination of the three aspects above or the paralleled analysis. Accordingly, in this paper, the study on the synthesized attributes of water use by regional vegetation in Southwest China was suggested, and the objectives of such a special study were clarified, targeting the following aspects: (i) characters of water consumption from transpiration of regional typical artificial vegetation; (ii) potential of water saving and drought resistance of regional typical artificial vegetation; (iii) effects of hydrological regulation of regional typical artificial vegetation; (iv) synthesized attributes of water use by regional typical artificial vegetation. It is expected to provide a new idea for the scientific assessment on the regional vegetation ecoenvironment effects and theoretical guidance for the regional vegetation reconstruction and ecological restoration

Investigation of hemorheological and analgesic properties of Qing-Nao tablets

Purpose: To investigate the hemorheological and analgesic potentials of Qing-Nao tablet (QNT).Methods: Sixty animals were divided into 6 groups (n = 10 for each group): normal, control, positive and 3 QNT-treated groups (QNT-H, QNT-M, QNT-L). Animals in normal and control groups received normal saline orally, while those in positive and QNT groups were orally administered either a suspension of the contents of Nao-luo-tong capsules or QNT. Hemorheological indices, including blood viscosity, plasma viscosity, activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time (PT) and fibrinogen (FIB), were determined. Acetic acid-induced writhing, tail tenderness and hot plate tests, as well as tests on microcirculation and balance/coordination were also carried out.Results: Acute toxicity results showed that QNT is a safe drug. Whole blood and plasma viscosities of the 3 QNT-treated groups significantly decreased (p < 0.05). However, TT levels of the 3 QNT-treated animals significantly increased (p < 0.05), whereas APTT and FIB values decreased significantly (p < 0.01). Moreover, QNT significantly increased analgesia in three animal models (p < 0.05). QNT-H also significantly improved balance and coordination abilities of mice (p < 0.05).Conclusion: These results demonstrate that QNT improves microcirculation and analgesia, and may be a source of promising candidate drugs for the treatment of brain concussion sequelae.Keywords: Qing-Nao tablet, Hemorheological, Analgesic effects, Brain concussion sequelae, Microcirculation, Balance and coordination abilitie

An ultra-sensitive and easy-to-use assay for sensing human UGT1A1 activities in biological systems

The human UDP-glucuronosyltransferase 1A1 (UGT1A1), one of the most essential conjugative enzymes, is responsible for the metabolism and detoxification of bilirubin and other endogenous substances, as well as many different xenobiotic compounds. Deciphering UGT1A1 relevance to human diseases and characterizing the effects of small molecules on the activities of UGT1A1 requires reliable tools for probing the function of this key enzyme in complex biological matrices. Herein, an easy-to-use assay for highly-selective and sensitive monitoring of UGT1A1 activities in various biological matrices, using liquid chromatography with fluorescence detection (LC-FD), has been developed and validated. The newly developed LC-FD based assay has been confirmed in terms of sensitivity, specificity, precision, quantitative linear range and stability. One of its main advantages is lowering the limits of detection and quantification by about 100-fold in comparison to the previous assay that used the same probe substrate, enabling reliable quantification of lower amounts of active enzyme than any other method. The precision test demonstrated that both intra- and inter-day variations for this assay were less than 5.5%. Furthermore, the newly developed assay has also been successfully used to screen and characterize the regulatory effects of small molecules on the expression level of UGT1A1 in living cells. Overall, an easy-to-use LC-FD based assay has been developed for ultra-sensitive UGT1A1 activities measurements in various biological systems, providing an inexpensive and practical approach for exploring the role of UGT1A1 in human diseases, interactions with xenobiotics, and characterization modulatory effects of small molecules on this conjugative enzyme. (c) 2020 Xi'an Jiaotong University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Peer reviewe

In Vivo Wound Healing Activity of Abrus cantoniensis

Abrus cantoniensis (Leguminosae sp.) is a traditionally used remedy for treating rheumatism, blood stasis, and internal injuries. In order to reveal a new insight of the utilization of the plant, solvent extraction by ethyl acetate (EA) was performed in order to evaluate the plant extracts’ in vivo excision and incision-wound potentials with models. The contents of the EA fraction, wound healing activity, acute oral toxicity, and acute dermal toxicity were studied. As a result, the main chemical constituents of the EA fraction were alkaloids, flavonoids, and steroids. The acute oral toxicity test results and assessment of skin hypoallergenicity showed that the plant extract was safe at LD50 as high as 5000 mg/kg. Both excision and incision model tests results indicated that the EA fraction of A. cantoniensis showed a significant wound healing capacity at a concentration of 5% (v/w) (p<0.01) as observed by the increased wound contraction, decreased epithelialization time, and increased hydroxyproline content compared to the ones of the controls. The present study showed that the EA fraction of A. cantoniensis possesses potential wound healing activities and provided recent results for the use of A. cantoniensis for wound curing