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- Author or Editor: Peng Zhang x
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This paper introduces and analyzes a new Chinese Manichaean painting entitled ‘Auspicious Signs Heralding Mānī’s Birth’. Zhang Peng 张鹏, a doctoral candidate at the Central Academy of Fine Arts (Zhongyang Meishu Xueyuan 中央美术学院), was the first to notice the Manichaean affiliation of this painting, which was auctioned by the Beijing Poly International Auction Co., Ltd (Beijing Baoli Guoji Paimai Youxian Gongsi 北京保利國際拍賣有限公司) in 2021. This study employs the methods of iconographic comparison and analysis of textual parallels to argue that the recently identified hagiographic painting shares striking stylistic similarities with at least three other previously known Manichaean paintings, and that it can be directly related to one of them.
Abstract
To optimize the hydration process of blended cement, cement clinker and supplementary cementitious materials (SCMs) were ground and classified into several fractions. Early hydration process of each cementitious materials fraction was investigated by isothermal calorimeter. The results show fine cement clinker fractions show very high hydration rate, which leads to high water requirement, while fine SCMs fractions present relatively high hydration (or pozzolanic reaction) rate. Cement clinker fractions in the range of 8–24 μm show proper hydration rate in early ages and continue to hydrate rapidly afterward. Coarse cement clinker fractions largely play “filling effect” and make little contribution to the properties of blended cement regardless of their hydration activity (or pozzolanic activity). The hydration process of blended cement can be optimized by arranging high activity SCMs, cement clinker, and low activity SCMs in fine, middle, and coarse fractions, respectively, which not only results in reduced water requirement, high packing density, and homogeneous, dense microstructure, but also in high early and late mechanical properties.
Abstract
Cu(nor)2·H2O (1), Zn(nor)2·4H2O (2), Ni(nor)2·2H2O (3), [Cu(nor)(phen)]NO3·4H2O (4), [Zn(nor)(phen)]NO3·2H2O (5), and [Ni(nor)(phen)]NO3·3H2O (6) were synthesized and their action on Tetrahymena growth was studied by microcalorimetry. The growth constant (k), inhibitory ratio (I), and half-inhibiting concentration (IC50) were calculated, which showed that the complexes had a strong inhibitory effect on Tetrahymena. All these complexes can inhibit the growth of Tetrahymena more strongly than norfloxacin. The norfloxacin–metal complexes exhibited better inhibitory activity than nor–phen–metal complexes. The power–time curves of Tetrahymena growth in the presence of norfloxacin were also measured. It was found that all complexes showed higher inhibitory activity than norfloxacin. And the inhibitory mechanism was discussed preliminarily. The diverse inhibition may be due to the ability of the complexes to penetrate into cells and the effect of these complexes on the nucleic acid. Microcalorimetry has been used extensively in many biological and chemical investigations as a universal, non-destructive, continuously running, and highly sensitive tool.
Abstract
A series of (o-alkylaminophenyl)diphenylphosphine ligands (P–N ligands) containing different alkyl carbon numbers or amino groups have been synthesized and characterized by IR and NMR (1H, 13C, 31P). The rhodium complexes ligated with P–N ligands in the hydroformylation of 1-hexene showed a considerable enhancement with the addition of water. NMR characterization studies suggested that the addition of water would engage in hydrogen bonding to the nitrogen atom of the coordinated P–N ligand, inhibiting the internal Rh–N interaction and generating more of the active unsaturated Rh-species that could react with 1-hexene to start the hydroformylation.
Abstract
The decomposition behavior of kaolin samples has been carried out by simultaneous TG–DTA experiments. New layer-structure formation during the calcination process was found, and metakaolin compound was detected between 600 and 900 °C. The thermal stability of kaolin samples was then identified by TG–DTA, and the results are confirmed by characterization of X-ray powder diffraction (XRD), N2 adsorption (Brunauer-Emmet-Teller model, BET), and scanning electron microscopy (SEM).
Abstract
Peroxynitrite is a potent oxidant in vivo which can result in serious diseases such as cardiopathy, acute inflammation and even cancer. Iron porphyrins have been shown to catalyze the efficient decomposition of peroxynitrite and are therefore important to detoxify the cytotoxic oxidant as therapeutic agents. A kinetic and theoretical study on peroxynitrite decomposition catalyzed by iron porphyrins is carried on in order to search and synthesize more effective scavengers of peroxynitrite. Kinetic experiments and quantum chemistry calculations were applied to iron porphyrins with different substituents for catalyzing peroxynitrite decay. Kinetic experiments suggested that the catalytic ability of iron porphyrins for peroxynitrite decomposition were dependent on the type and location of substituents on the porphyrin rings. Density functional calculations further reveal that the variation of substituent leads to a difference in structure-related quantum chemical descriptors including charges of central metal ion, energy of the highest occupied molecular orbital and energy of the lowest unoccupied molecular orbital.
Abstract
This study focused on developing an effective and environmentally friendly method to measure ligustrazine in rat serum by using polymer monolith micro-extraction (PMME) technique. A poly (methacrylic acid-ethylene glycol dimethacrylate) material was used to extract ligustrazine through hydrophobic and ion-exchange interaction. Qualitative and quantitative analysis was performed by a liquid chromatography and tandem mass spectrometry. After optimization of several PMME conditions, the developed method exhibited excellent extraction performance to the ligustrazine. Good linearity was acquired ranging from 10 to 2,000 ng mL−1, and the limit of detection of the proposed method was 0.14 ng mL−1. The recoveries measured by spiking three different concentrations in rat serum ranged from 82.6 to 95.3%, and excellent precision was found with relative standard deviations (RSDs) less than 8.3% for intra-day and 9.7% for inter-day, respectively. At last, the applicability of the method was further confirmed through continuous monitoring of ligustrazine in rat serum after dosing of ligustrazine tablets to rats.
Investigation on human resource role is progressing, and the influence of fits between human resources and business strategies have been confirmed in various studies. Such influence has also been proven as a good way to acquire organizational competitive advantages and achieve the optimal operating performance. Under such a context, a new variable, Management Innovation, is included in this study to observe the effects of such a practical and changeable variable on strategic orientation and human resource management role.
Top ten businesses in Fujian Province are selected for the questionnaire survey. Total 500 copies of questionnaire are distributed and 376 valid copies are retrieved, with the retrieval rate 75%. The research results show the positive effects of 1. strategic orientation on management innovation, 2. strategic orientation on human resource management role, and 3. management innovation on human resource management role. It expects to verify richer and multiple effects in this study for the reference of successive research and the practice.
Summary
A new high-performance liquid chromatography (HPLC) method has been developed and validated for determination of enantiomeric purity of thiazolidine-2-carboxylic acid within a short run time of less than 10 min. The method was based on pre-column derivatization of thiazolidine-2-carboxylic acid with aniline, and complete separation of enantiomers has been achieved on a Chiralcel OD-H analytical column (250 × 4.6 mm) using n-hexane-isopropanol (85:15 v/v) as mobile phase at a flow rate of 1.0 mL min−1 under UV and optical rotation (OR) detection. Detection wavelength was set at 254 nm. Then the effects of mobile phase and temperature on enantioselectivity were further evaluated. The method was validated with respect to precision, accuracy, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The recoveries were between 98.5 and 101.3% with percentage relative standard deviation less than 1.16%. The LOD and LOQ for the aniline derivatives of (+)-thiazolidine-2-carboxylic acid were 4.9 and 16.4 μg mL−1 and for the aniline derivatives (−)-thiazolidine-2-carboxylic acid were 5.1 and 17.2 μg mL−1, respectively.
Abstract
Objective
This study aimed to assess the expression of NCAPH in human breast cancer, and to investigate its effects on breast cancer cells.
Methods
Bioinformation analysis was performed to analyze the expression of NCAPH in human breast cancer tissues and normal tissues in TCGA database. qPCR and Immunoblot assays were performed to clarify the expression of NCAPH in breast cancer tissues and cell lines, respectively. CCK-8, colony formation, FCM, transwell, and immunoblot assays were performed to reveal the effects of NCAPH on breast cancer proliferation, cell cycle, motility and EMT of breast cancer cells. Additionally, immunoblot assays were performed to investigate the effects of NCAPH on the PI3K/AKT pathway in breast cancer.
Results
We found that NCAPH was highly expressed in human breast cancer cell lines. The depletion of NCAPH suppressed the viability of breast cancer cells. Further, we noticed that its downregulation restrained breast cancer cell migration as well as invasion, and the EMT process. Mechanically, we noticed that NCAPH mediated the PI3K/AKT pathway, and therefore contributed to breast cancer progression.
Conclusion
In summary, NCAPH has the potential to serve as a breast cancer target.